Honda Cbr150

[taichiplanet]

Okay, anyone have a bike and rule handy that can measure up the rear end clearance? Basically we need 152mm (142 + 5 +5).

There is a forum on http://www.cbr150club.com/board/index.php?topic=9736.0 about Machimura 2.5 and 3.5” rims, there is a photo of a modified CBR 150 rear end with the rim and a bigger tyre but it has a different swing arm fitted. No other shots of larger tyres, just the typical skinny ones! On page 4 someone is talking about the Pirelli 130/70 but it is all in Thai so I ain’t got the foggiest. They also seem to be mentioning 100/80 on the front too.

[visions]

Okay, anyone have a bike and rule handy that can measure up the rear end clearance? Basically we need 152mm (142 + 5 +5).

There is a forum on http://www.cbr150club.com/board/index.php?topic=9736.0 about Machimura 2.5 and 3.5" rims, there is a photo of a modified CBR 150 rear end with the rim and a bigger tyre but it has a different swing arm fitted. No other shots of larger tyres, just the typical skinny ones! On page 4 someone is talking about the Pirelli 130/70 but it is all in Thai so I ain't got the foggiest. They also seem to be mentioning 100/80 on the front too.

I just measured the clearances.....there is 20mm clearance to the chain guard from the widest point of the tyre, and the inside of the chain is basicly even with the guard. The swing arm is about 40mm clearance at the widest point of the tyre.

My almost new std 100 rear tyre is about 97mm wide. I have a bigger bike with Dunlop 120 front and 140 rear. They measure 120mm and 140mm wide so I presume a 130 tyre would measure 130mm wide??? That means a 130 section tyre is 15mm wider from centre line to outside.than my present 100 rear. We have 20mm clearance so close, but I think get away with a 130 ok.

The overall diameter of a 130/80 is the same as the 100/80 (the 80 is 80mm depth and same for both tyres) so no gearing issues arise, except if get some ballooning fitting to the narrower than desired rim. That would add to the overall diameter slightly.

I am a definate buyer of wider section tyres so if anyone finds a supply I will happily join in to increase purchase bargining power... Bkk or Eastern area.

[canuckamuck]

I don't think you will have an issue with the sidewall clearance on a 130 tire. But you are going to have to consider the tread getting past the crotch of the swingarm. My 120 leaves about 4mm with very little adjustment left to slide the tire back. I am not sure I could get it to 8mm.

[taichiplanet]

Okay, anyone have a bike and rule handy that can measure up the rear end clearance? Basically we need 152mm (142 + 5 +5).

There is a forum on http://www.cbr150club.com/board/index.php?topic=9736.0 about Machimura 2.5 and 3.5" rims, there is a photo of a modified CBR 150 rear end with the rim and a bigger tyre but it has a different swing arm fitted. No other shots of larger tyres, just the typical skinny ones! On page 4 someone is talking about the Pirelli 130/70 but it is all in Thai so I ain't got the foggiest. They also seem to be mentioning 100/80 on the front too.

I just measured the clearances.....there is 20mm clearance to the chain guard from the widest point of the tyre, and the inside of the chain is basicly even with the guard. The swing arm is about 40mm clearance at the widest point of the tyre.

My almost new std 100 rear tyre is about 97mm wide. I have a bigger bike with Dunlop 120 front and 140 rear. They measure 120mm and 140mm wide so I presume a 130 tyre would measure 130mm wide??? That means a 130 section tyre is 15mm wider from centre line to outside.than my present 100 rear. We have 20mm clearance so close, but I think get away with a 130 ok.

The overall diameter of a 130/80 is the same as the 100/80 (the 80 is 80mm depth and same for both tyres) so no gearing issues arise, except if get some ballooning fitting to the narrower than desired rim. That would add to the overall diameter slightly.

I am a definate buyer of wider section tyres so if anyone finds a supply I will happily join in to increase purchase bargining power... Bkk or Eastern area.

The info i got from Michelin Uk was that the 130 tyre measured 142mm, and dave-boo reckons we need 5mm clearance either side, so we need a total of 152mm.

The 80 is the profile (or aspect ratio) of the tyre which is calculated on the ratio of tyre width and tyre height so a 130/80 tyre will have a different rolling diameter than a 100/80, which is what effects gearing. http://www.toyo.com.au/tech_info17.htm

[PeaceBlondie]

I'm planning to put new Michelins on my totally stock CBR150 soon. Maybe 80% aspect ratio, and 10 mm wider, front and rear. So tell me again please: stock, what have I? I see no need for super wide.

[dave_boo]

So I was pondering the question of going big tyre on the front. On the one hand, it will negative affect steering. On the other, with a judicious use of math, we can alter the trail of the wheel itself and get back the handling.

Easiest way to modify the trail is to shorten the forks. I.E., loosen the triple clamps and move the forks up into the air. This changes the head angle, causing it to be closer to 0 degrees (nearly vertical). In my blatant theft of the formula from Wikipedia; R_w=wheel radius, A_h=head angle measured clock-wise from the horizontal and O_f=fork offset or rake.

Now, temporarily disregarding the width of the newer tyres, we know that a 80/90 has a height of 72mm. 100/80 has 80mm height. Also, the fork offset will not change. So, if we merely use the 72mm and the 80mm we end up with this equation (where R_w1=radius of the original tyre, R_w2=width of the new tyre and A_h-X_h=head angle when you move the forks up past their original height).

(R_w2cos(A_h-X_h))/sin(A_h-X_h)=Trail=(R_w1cos(A_h))/sin(A_h)

Trig tells us that cos(X)/sin(X)=cot(X) so we can simplify the equation down to this:

R_w2cot(A_h-X_h)=R_w1cot(A_h)

Reducing that down further we get:

cot(-X_h)=R_w1/R_w2 or X_h=-tan(R_w1/R_w2)

So, to go from a 80/90 to a 100/80 and keep your same trail, you need to decrease your head angle by 1.26 degrees. And for those wondering why you actually get a negative number, it is because the measurement of the head angle is from horizontal clock-wise. So when you plug that 1.26 in to the formula, the A_h needs to increase so that the head is more vetical. If the A_h was measured from the vertical, it would by necessity have to decrease.

That was the complicated math.

However, even though we have our angle that the head needs to come towards vertical, we don't know how far the forks need to be raised to get that angle. You of course could attempt to measure your current A_h and keep moving the forks in until you reach the proper angle, or you could do the math.

Per various websites, we can see the rake (A_h) is 25 degrees and the trail is 88mm. General rule of thumb (once again stolen from Wikipedia) is that 10mm fork lenght change results in 1/2 degree rake (A_h) change. So we want 1.26*10mm, or 12.6mm (0.496 or 1/2 inch for us Yanks) of the fork sticking out of the top clamp and the trail for the larger tyres will be back to Honda's design.

Now, the big question is; how much does the width affect the liveliness of the steering? Is it a direct relationship, log or what? Add in the variables of different tyre design (some are rounder and some are sharper) and there's a lot of trial and error.....

I just measured the clearances.....there is 20mm clearance to the chain guard from the widest point of the tyre, and the inside of the chain is basicly even with the guard. The swing arm is about 40mm clearance at the widest point of the tyre.

My almost new std 100 rear tyre is about 97mm wide. I have a bigger bike with Dunlop 120 front and 140 rear. They measure 120mm and 140mm wide so I presume a 130 tyre would measure 130mm wide??? That means a 130 section tyre is 15mm wider from centre line to outside.than my present 100 rear. We have 20mm clearance so close, but I think get away with a 130 ok.

The overall diameter of a 130/80 is the same as the 100/80 (the 80 is 80mm depth and same for both tyres) so no gearing issues arise, except if get some ballooning fitting to the narrower than desired rim. That would add to the overall diameter slightly.

I am a definate buyer of wider section tyres so if anyone finds a supply I will happily join in to increase purchase bargining power... Bkk or Eastern area

No, the 80 is a percentage of the width. The 130/80 is actually 104mm tall and the 100/80 is 80 mm tall. There's a big difference there and will affect the gearing.

I don't think you will have an issue with the sidewall clearance on a 130 tire. But you are going to have to consider the tread getting past the crotch of the swingarm. My 120 leaves about 4mm with very little adjustment left to slide the tire back. I am not sure I could get it to 8mm.

What's the ratio? 120/?. This will let us know exactly which tyres we can fit on there. If it's 120/80, than the best that those dreaming about 130 section tyres are going to do is 130/70...

I'm planning to put new Michelins on my totally stock CBR150 soon. Maybe 80% aspect ratio, and 10 mm wider, front and rear. So tell me again please: stock, what have I? I see no need for super wide.

80/90 front and 100/80 rear. Going 90/80 front will keep your speedo running at the same-same speed as before. Going 110/70 on the rear would keep that tyre the same height. To be honest though, I think if we group bought the 100/70 front and 120/80 we'd all be sitting pretty well on a nice discount....

[visions]

So I was pondering the question of going big tyre on the front. On the one hand, it will negative affect steering. On the other, with a judicious use of math, we can alter the trail of the wheel itself and get back the handling.

Easiest way to modify the trail is to shorten the forks. I.E., loosen the triple clamps and move the forks up into the air. This changes the head angle, causing it to be closer to 0 degrees (nearly vertical). In my blatant theft of the formula from Wikipedia; R_w=wheel radius, A_h=head angle measured clock-wise from the horizontal and O_f=fork offset or rake.

Now, temporarily disregarding the width of the newer tyres, we know that a 80/90 has a height of 72mm. 100/80 has 80mm height. Also, the fork offset will not change. So, if we merely use the 72mm and the 80mm we end up with this equation (where R_w1=radius of the original tyre, R_w2=width of the new tyre and A_h-X_h=head angle when you move the forks up past their original height).

(R_w2cos(A_h-X_h))/sin(A_h-X_h)=Trail=(R_w1cos(A_h))/sin(A_h)

Trig tells us that cos(X)/sin(X)=cot(X) so we can simplify the equation down to this:

R_w2cot(A_h-X_h)=R_w1cot(A_h)

Reducing that down further we get:

cot(-X_h)=R_w1/R_w2 or X_h=-tan(R_w1/R_w2)

So, to go from a 80/90 to a 100/80 and keep your same trail, you need to decrease your head angle by 1.26 degrees. And for those wondering why you actually get a negative number, it is because the measurement of the head angle is from horizontal clock-wise. So when you plug that 1.26 in to the formula, the A_h needs to increase so that the head is more vetical. If the A_h was measured from the vertical, it would by necessity have to decrease.

That was the complicated math.

However, even though we have our angle that the head needs to come towards vertical, we don't know how far the forks need to be raised to get that angle. You of course could attempt to measure your current A_h and keep moving the forks in until you reach the proper angle, or you could do the math.

Per various websites, we can see the rake (A_h) is 25 degrees and the trail is 88mm. General rule of thumb (once again stolen from Wikipedia) is that 10mm fork lenght change results in 1/2 degree rake (A_h) change. So we want 1.26*10mm, or 12.6mm (0.496 or 1/2 inch for us Yanks) of the fork sticking out of the top clamp and the trail for the larger tyres will be back to Honda's design.

Now, the big question is; how much does the width affect the liveliness of the steering? Is it a direct relationship, log or what? Add in the variables of different tyre design (some are rounder and some are sharper) and there's a lot of trial and error.....

I just measured the clearances.....there is 20mm clearance to the chain guard from the widest point of the tyre, and the inside of the chain is basicly even with the guard. The swing arm is about 40mm clearance at the widest point of the tyre.

My almost new std 100 rear tyre is about 97mm wide. I have a bigger bike with Dunlop 120 front and 140 rear. They measure 120mm and 140mm wide so I presume a 130 tyre would measure 130mm wide??? That means a 130 section tyre is 15mm wider from centre line to outside.than my present 100 rear. We have 20mm clearance so close, but I think get away with a 130 ok.

The overall diameter of a 130/80 is the same as the 100/80 (the 80 is 80mm depth and same for both tyres) so no gearing issues arise, except if get some ballooning fitting to the narrower than desired rim. That would add to the overall diameter slightly.

I am a definate buyer of wider section tyres so if anyone finds a supply I will happily join in to increase purchase bargining power... Bkk or Eastern area

No, the 80 is a percentage of the width. The 130/80 is actually 104mm tall and the 100/80 is 80 mm tall. There's a big difference there and will affect the gearing.

I don't think you will have an issue with the sidewall clearance on a 130 tire. But you are going to have to consider the tread getting past the crotch of the swingarm. My 120 leaves about 4mm with very little adjustment left to slide the tire back. I am not sure I could get it to 8mm.

What's the ratio? 120/?. This will let us know exactly which tyres we can fit on there. If it's 120/80, than the best that those dreaming about 130 section tyres are going to do is 130/70...

I'm planning to put new Michelins on my totally stock CBR150 soon. Maybe 80% aspect ratio, and 10 mm wider, front and rear. So tell me again please: stock, what have I? I see no need for super wide.

80/90 front and 100/80 rear. Going 90/80 front will keep your speedo running at the same-same speed as before. Going 110/70 on the rear would keep that tyre the same height. To be honest though, I think if we group bought the 100/70 front and 120/80 we'd all be sitting pretty well on a nice discount....

Well I never went to school long enough to understand the maths, but I am practical enough to understand the reasoning

yes count me in as a starter on a group buy of 100/70 120/80 set up.

I would also love to hear from anyone that has done the bore up to 180cc or the stroker to 197cc.....how was the end result??

Im also looking at upgrading to 296 front disc and brembo calipers also. I believe stopping faster.....is more important that going faster.

Oh..... if only Honda put a 250 twin in this bike!! rekin it would have to be the perfect commuter then!!

[canuckamuck]

My bike's rear is 120/80, Dave. I think your estimation that 130/70 would be the max possible is correct. Unless you want to extend the swing arm.

[taichiplanet]

So dave_boo, tells us what you really think! I had to stop half way through reading your calculations and wipe the brain matter from the screen due to my puny brain exploding! I'd still be interested in seeing if i can go the 130/70 rear. Which means i need to find a 3.50" rear rim, maybe a 3.00' rear rim at a pinch. I see the advantage of not switching rims, but the Pirelli 120/80 is a front tyre so that is not a problem?

Peace the original tyres are 80/90 front and 100/80 rear. With the Michelin Pilot Sporty go for the 90/80 front and 100/80 rear, which is what i have at the moment, you will love your bike even more. The ride and handling is sooo much better mainly due to the softer rubber.

Cannuckamuck, the 120/80 has a rolling diameter of 621mm, the 130/70 has a rolling diameter of 615mm, which you can see is smaller! The factory fitted rear 90/80 tyre has a rolling diameter of about 585mm.

Just a more practical idea. Maybe if someone could please try this to see if the 130/70 will fit: get something like a wooden skewer from a fruit stall, cut it down to 152mm, tape it to inside of the rim so that it sticks out both sides equally (or if you can work out the centre line of the tyre, stick the stick on top of the tyre), raise the bike up so the rear wheel is off the ground and slowly rotate the wheel to see If it hits anywhere. If it does hit make sure the stick is in the right place, if it is, then work out how much you need to take off to get clearance. That should be a fairly definitive way to see what clearance we have; unless I’m horribly wrong!

I hope to get my bike back latter this week with the 180cc motor; hopefully it won't be a problem.

[thaicbr]

BLEMEY............. You lot aint listening. The 130 does fit but on my bike it had a slow leak, that could have been porous rims, bead problem or just plain and simple it was to big.

I believe that it was to big because it had a very round profile. If i were you guys i would get together a list of who wants the 110 rear then talk to Golila on Mocyc and tell him. He might try harder to get them into stock if he knows he can sell say 10 in one go. Just a thought. The 110 is what i would go for if available. I think the 130 though good handling was a little to large for the power available. the 110 would be perfect.

[dave_boo]

Well I never went to school long enough to understand the maths, but I am practical enough to understand the reasoning

It's not that hard, just basic trig...

yes count me in as a starter on a group buy of 100/70 120/80 set up.

Good! Let's try and get a few more people.

I would also love to hear from anyone that has done the bore up to 180cc or the stroker to 197cc.....how was the end result??

Im also looking at upgrading to 296 front disc and brembo calipers also. I believe stopping faster.....is more important that going faster.

Well, as mine is out of warranty now (3 years!), I was considering it. Even thought about buying a replacement motor from Honda and upgrading it; that way I could quickly swap the original motor in when it's time to go to the DMV.

Oh..... if only Honda put a 250 twin in this bike!! rekin it would have to be the perfect commuter then!!

There's always the VTR 250...but that's expensive.

My bike's rear is 120/80, Dave. I think your estimation that 130/70 would be the max possible is correct. Unless you want to extend the swing arm.

I thought so...even at 120/80 the height of the sidewall is 32mm (20% taller than the stock); it may look funny.

So dave_boo, tells us what you really think! I had to stop half way through reading your calculations and wipe the brain matter from the screen due to my puny brain exploding! I'd still be interested in seeing if i can go the 130/70 rear. Which means i need to find a 3.50" rear rim, maybe a 3.00' rear rim at a pinch. I see the advantage of not switching rims, but the Pirelli 120/80 is a front tyre so that is not a problem?

I don't believe that there would be there would be an issue with the CBR 150R using a front tyre from a big bike on the rear; these tyres are designed for bikes that put much more stress than the 20 odd horsepower that our bikes put out. Having stated that (and I've been wrong before!), going with the Pirelli Sport Demons in size 100/80 (front) and 120/80 rear may be a good option for us.

Peace the original tyres are 80/90 front and 100/80 rear. With the Michelin Pilot Sporty go for the 90/80 front and 100/80 rear, which is what i have at the moment, you will love your bike even more. The ride and handling is sooo much better mainly due to the softer rubber.

Cannuckamuck, the 120/80 has a rolling diameter of 621mm, the 130/70 has a rolling diameter of 615mm, which you can see is smaller! The factory fitted rear 90/80 tyre has a rolling diameter of about 585mm.

6mm difference isn't much when you're talking about rolling diameter...would only change the gear ratio some 0.0096.

Just a more practical idea. Maybe if someone could please try this to see if the 130/70 will fit: get something like a wooden skewer from a fruit stall, cut it down to 152mm, tape it to inside of the rim so that it sticks out both sides equally (or if you can work out the centre line of the tyre, stick the stick on top of the tyre), raise the bike up so the rear wheel is off the ground and slowly rotate the wheel to see If it hits anywhere. If it does hit make sure the stick is in the right place, if it is, then work out how much you need to take off to get clearance. That should be a fairly definitive way to see what clearance we have; unless I'm horribly wrong!

The 130 fits, see thaiCBR's postings.

I hope to get my bike back latter this week with the 180cc motor; hopefully it won't be a problem.

BLEMEY............. You lot aint listening. The 130 does fit but on my bike it had a slow leak, that could have been porous rims, bead problem or just plain and simple it was to big.

I believe that it was to big because it had a very round profile. If i were you guys i would get together a list of who wants the 110 rear then talk to Golila on Mocyc and tell him. He might try harder to get them into stock if he knows he can sell say 10 in one go. Just a thought. The 110 is what i would go for if available. I think the 130 though good handling was a little to large for the power available. the 110 would be perfect.

And thaichiplanet is talking about getting differet rims....

[Sentinel66]

Hello All

Well my parts came in today and I'm chomping at the bit to get some of the mods done; my buddie's mechanic is tied up at the moment and can't get to it anytime soon so he's referring me to a freind of his to do the work, yada yada yada ... In the meantime I figured I'd tackle one or 2 small things I figured I could do myself - namely replacing the exhaust and replacing the stock air box/filter with a new K&N filter. So I got the faring off and managed to replace the pipe/exhause without issue, but when I went to look at getting at the carb to do the air filter I saw that it was burried under the seat/tank/between the frame - yikes! Is there an obvious way to get to the air filter that I'm missing or does the tank need to be removed first to do this work? if so how involved it this to do?

Thanks for any advice!

[T_Dog]

There is a little welded on dog on the swing arm, exhaust side. (See the pics below.) Anyone know what this is for? A fellow -150 owner thought it might be used during shipping to keep the shock compressed.

[songoku777]

This is how a 130/70x17 and a 110/70x17 tire would look on the stock CBR rims...

A tire too bulky on a skinny rim will just make it look good but most of the tire tread is useless as it already forms part of the tire's wall.

The biggest tire i've seen on a stock CBR150 (with no other mods but making the chain longer) is a 140/60x17.. and it already looks funny.

personally, i prefer the 100/80x17 ...

Good contact patch given the current rim configuration; and maximizes the power to weight ratio of the 150cc multivalve mini sportbike ^^

Used to have a 110/70 rear, i put back the old 100/80.. my caliper told me the latter 'will look' wider by ±3mm and is lower by ±2mm. HTH.

Edited July 20, 2009 by songoku777

[canuckamuck]

Hello All

Well my parts came in today and I'm chomping at the bit to get some of the mods done; my buddie's mechanic is tied up at the moment and can't get to it anytime soon so he's referring me to a freind of his to do the work, yada yada yada ... In the meantime I figured I'd tackle one or 2 small things I figured I could do myself - namely replacing the exhaust and replacing the stock air box/filter with a new K&N filter. So I got the faring off and managed to replace the pipe/exhause without issue, but when I went to look at getting at the carb to do the air filter I saw that it was burried under the seat/tank/between the frame - yikes! Is there an obvious way to get to the air filter that I'm missing or does the tank need to be removed first to do this work? if so how involved it this to do?

Thanks for any advice!

Use your key take out the pillion seat, from there you will see how to take off the main seat. The tank is next, disconnect the fuel any electrical lines. then the airbox is wide open for you to do whatever. When you put the tank back on be super careful as it is very easy to scratch the sides or your mid faring. It is really best to have a second pair of hands for this step.

[songoku777]

Stock tire sizes are all the CBR150 circuit bikes need. Notice the fully utilized tread...

good ol' Dunlops.

[dave_boo]

Stock tire sizes are all the CBR150 circuit bikes need. Notice the fully utilized tread...

good ol' Dunlops.

I'm pretty sure that none of us in this thread can match those track riders. Add in the smooth tracks and I'm sure they can get away with it. For us mere mortals who are going to be commuting on the bikes, the added rubber is an advantage.

**edit**

Up in post 1181, I meant to say 120/70.

Edited July 20, 2009 by dave_boo

[jbeck]

I agree that adding a "bigger" tire(s) (that weighs more) WILL make the bike handle worse and also make it accelerate and change direction slower.

They will add protection from road hazards and look cooler.

If you have the money to experiment with different sizes of tires, that's cool. You could get used ones first, to try out.

What you really want for performance is a soft, sticky tire, that will reach it's designed operating temperature quickly.

Even tho racing tires are sticky, many are engineered to heat up ONLY at continuous high speed which makes them stay cold on the street, unless you don't have to stop! (doi suthep?) Anyone know where to buy Vee brand tires in Chiang Mai and what sizes/models will fit properly?

If the sides of your tires aren't worn, this whole discussion seems irrelevant.

I want to know if 47,000B is a good price for a used (only 500KM) 2008 CBR150RR from a honda dealer ( A mechanic who works there)

thanks.

Jeff Beck

[jbeck]

I want to know if 47,000B is a good price for a used (only 500KM) 2008 CBR150RR from a honda dealer ( A mechanic who works there).

It looks perfect. Has anyone ridden a "good" late model sonic and are they close in acceleration or top speed?

How close?

Anyone know (from EXPERIENCE) the top speed of either?

thanks,

Jeff Beck

[canuckamuck]

I want to know if 47,000B is a good price for a used (only 500KM) 2008 CBR150RR from a honda dealer ( A mechanic who works there).

It looks perfect. Has anyone ridden a "good" late model sonic and are they close in acceleration or top speed?

How close?

Anyone know (from EXPERIENCE) the top speed of either?

thanks,

Jeff Beck

Yes it is a good price.

Top indicated speed on my CBR 150 is about 140 crouched.

Never ridden a Sonic though

[dave_boo]

That's a really good price for a hardly used CBR. I'd be suspicous though....go over it thoughly!

I've ridden both a late model Sonic and my CBR. Even ridden an earlier model Sonic with a CBR top end on it. To be honest, the gearing on the suped up Sonic easily bested the CBR....but it didn't have the same-same top speed; I believe my mate had different sprockets on it. Wheelied easily enough though.

The stock Sonic seems to be more sluggish than a CBR, perhaps similar gearing(?), and I didn't take it up to top speed since it's the wife's uncle's ride. The top speed of either is most likely limited to gearing and the fact that the CBR is more stable. No use taking a Sonic up to an equivalent top speed if you feel like you're going to lose control of it.

One thing to consider; inside the city there's a chance that the Sonic would be a better bike. But you're still sitting upright on an step-through bike. Also, you give up a front basket that you'd get on say a Wave or another stepthough. I think that in and of itself would discourage me from considering a Sonic over a CBR.

[jbeck]

That's a really good price for a hardly used CBR. I'd be suspicous though....go over it thoughly!

I've ridden both a late model Sonic and my CBR. Even ridden an earlier model Sonic with a CBR top end on it. To be honest, the gearing on the suped up Sonic easily bested the CBR....but it didn't have the same-same top speed; I believe my mate had different sprockets on it. Wheelied easily enough though.

The stock Sonic seems to be more sluggish than a CBR, perhaps similar gearing(?), and I didn't take it up to top speed since it's the wife's uncle's ride. The top speed of either is most likely limited to gearing and the fact that the CBR is more stable. No use taking a Sonic up to an equivalent top speed if you feel like you're going to lose control of it.

One thing to consider; inside the city there's a chance that the Sonic would be a better bike. But you're still sitting upright on an step-through bike. Also, you give up a front basket that you'd get on say a Wave or another stepthough. I think that in and of itself would discourage me from considering a Sonic over a CBR.

the sonic is roughly 20,000B less than the cbr (both new), and tons of performance parts are avail for both. The sonic is way lighter and the only (other) bike i would consider for performance riding for fun and adrenaline, like doi suthep. I'm not thinking about the comparison to an automatic or strictly in-town bike. Both would never win that category. I drove a cbr and was a little disappointed - it wasn't fast enough! I was wondering if the sonic is anywhere close, being much lighter, and with only a 2-valve head, but still having the right size wheels, disc brakes, and 6 speeds. Yes and a slight advantage in town. Also the sonic can be fitted with a steering damper for high speed worries.

I'd like to be able to go 125 easily, and top out around 140, and do wheelies.

I um, have a problem, I used to race and, so I need to go fast - well, I actually just decided this after modifying an airblade heavily, I'm waiting to see what happened but I think I can solve part of the problem by starting with a more 'real' bike to begin with (not an automatic).

Anyone interested in a 2008 mag wheel, 5000KM airblade, with a 25,000 Baht complete engine modification (matched kit): cylinder, ported head, bigger valves, piston, cam, much larger carburetor w/proper jetting, intake manifold, K&N style filter, complete stainless steel exhaust pipe, larger battery, billet levers, etc...?

[dave_boo]

You may want to remove your email addy if you don't want to get spammed....there's all sorts of bots that troll forums and harvest addies just to do that.

The Sonic is some 25kg lighter than the CBR (per Wikipedia's numbers), and shares much of the same same go-fast parts as the bigger bike. I't also some 2/3 the power of the CBR. It will go 125 (indicated anyways) but I'd be nervous at a 'real' 140.

If you're really interested in speed, find yourself a nice clean NSR 150. I'm assuming your budget is in the 45 000 THB range, and you can easily pick a tip-top example of one up for 15 000 THB and then spend the remaining rebuilding everything to new standards. Mid-20's HP at the rear wheel stock and a light weight means that it will eat either of the bikes you mentioned for lunch (and most likely the Ninja 250s running around too). 30 real HP should be easily within reach and a lot more fun than the boring four stroke gradual progression of power. Add in the simplicity of the design and the many parts available and it's going to be cheap to run.

[jbeck]

You may want to remove your email addy if you don't want to get spammed....there's all sorts of bots that troll forums and harvest addies just to do that.

The Sonic is some 25kg lighter than the CBR (per Wikipedia's numbers), and shares much of the same same go-fast parts as the bigger bike. I't also some 2/3 the power of the CBR. It will go 125 (indicated anyways) but I'd be nervous at a 'real' 140.

If you're really interested in speed, find yourself a nice clean NSR 150. I'm assuming your budget is in the 45 000 THB range, and you can easily pick a tip-top example of one up for 15 000 THB and then spend the remaining rebuilding everything to new standards. Mid-20's HP at the rear wheel stock and a light weight means that it will eat either of the bikes you mentioned for lunch (and most likely the Ninja 250s running around too). 30 real HP should be easily within reach and a lot more fun than the boring four stroke gradual progression of power. Add in the simplicity of the design and the many parts available and it's going to be cheap to run.

As a previous RS250 racer and NSR250 owner, I thought i would love the nsr150. I tried, but cant find a clean , nice nsr150 SP.

They're all very old and beat down and I like my stuff almost new.

Also the seating position is terrible, really long reach to the bars and hard on the wrists (odd for a 150) and completely sucks around town.

how do I remove my post/address?

[dave_boo]

If you're really nice to him (like send him chocolates), perhaps PeaceBlondie will edit your posts.

I do understand your concerns about the used bikes in Thailand. Have you searched through www.mocyc.com? (this one looks pretty nice) There's a lot to wade through, but when I just looked, there seems to be some nice NSRs on there.

You do have interesting requirements though; a short reach, cheap, newish, and fast. There's something not computing about that. Just considering the last three, you can only get two out of three of those options on a bike in Thailand.

[thaicbr]

Me. I'm getting a Yamaha TZM150 to play with. Waiting to get one at the moment 6,000baht then spend another 5,000 to get it up to spec. I'm thinking of using the upside down forks off the tiger250 just to spice it up a bit (that will add a bit to the rebuild though)

Edited July 20, 2009 by thaicbr

[phobic]

Hey, just ordered some parts from akunar ( 28mm carb, clutch plates/hd springs and ajustable levers ).. i have a yet another question. Im thinking of buying a new drive chain too. I see in the service manual that the stock chain is a DID 428VI-124LE, now i understand the 428 bit.. what does all the other numbers/letters mean? I looked up some chains on the net and found some 428 models but they dont have the same numbers/letters that the stock one have.

Will there be any problems if i buy lets say a DID 428H 126L?

**edit** I found out that it was a mix of the tensioner for the timing chain and the springs for the clutch that caused the issue i had before, springs where in bad shape and the timing chain was too loose.. thanks for helping me with that guys. **

Thanks

Edited July 20, 2009 by phobic

[dave_boo]

The 124 tells you how many links and I believe that the "E" stands for economy.

"VI" I'm not sure of, the DID website doesn't list that designation....perhaps a Honda specific code?

**edit**

You may also want to replace your sprockets at the same time...it's not a bad idea to ensure the best possible life out of your new chain.

Edited July 20, 2009 by dave_boo

[jbeck]

The 124 tells you how many links and I believe that the "E" stands for economy.

"VI" I'm not sure of, the DID website doesn't list that designation....perhaps a Honda specific code?

**edit**

You may also want to replace your sprockets at the same time...it's not a bad idea to ensure the best possible life out of your new chain.

one or more of the letters usually means the type of rubber seal - O-ring, X-ring, Z-ring, or in some case, no rubber seal, also there is/can be a number/letter indicating the max engine size or whether it's for dirt/street/etc.. this depends on the manufacturer, just look at their web site(s). buy the best chain you can get.

[jbeck]

If you're really nice to him (like send him chocolates), perhaps PeaceBlondie will edit your posts.

I do understand your concerns about the used bikes in Thailand. Have you searched through www.mocyc.com? (this one looks pretty nice) There's a lot to wade through, but when I just looked, there seems to be some nice NSRs on there.

You do have interesting requirements though; a short reach, cheap, newish, and fast. There's something not computing about that. Just considering the last three, you can only get two out of three of those options on a bike in Thailand.

In mocyc.com, what did you search on? I put nsr in the search box and got no results with nsr motorcycles. can you read thai?

thanks. Cheap is relative. If a used low miles sonic is 30,000B, I can put 20000B in the sonic and have quite a nice special bike.

To add parts to the CBR would put me in the 70000B range.

I'm thinking CDI, cyl, head, pipe, piston, cam, rearsets, tires, chain, sprockets, levers, shock.

thanks,

Jeff