Cbr150 Sprocket Changed

[sinewave]

Got a rear flat today, so decided to experiment with sprocket ratios while at it. I went from a 16/42 to a 15/44 ratio and the difference was very noticeable, i'd honestly say about 15-20% increase in torque. The bottom end from standstill is more bold and quite a bit more powerful and the bikes exhaust note is deeper also, and it feels like a totally different bike now. In a good way.

Total cost for inner tube and front sprocket, rear sprocket and chain including labor 600 baht.

Give it a try you'll like it

[Thai Chi]

Got a rear flat today, so decided to experiment with sprocket ratios while at it. I went from a 16/42 to a 15/44 ratio and the difference was very noticeable, i'd honestly say about 15-20% increase in torque. The bottom end from standstill is more bold and quite a bit more powerful and the bikes exhaust note is deeper also, and it feels like a totally different bike now. In a good way.

Total cost for inner tube and front sprocket, rear sprocket and chain including labor 600 baht.

Give it a try you'll like it

Have you noticed any loss in "top end" speed though ??

[BigBikeBKK]

Total cost for inner tube and front sprocket, rear sprocket and chain including labor 600 baht.

Man ya gotta LOVE Thailand!!!

[neverdie]

Total cost for inner tube and front sprocket, rear sprocket and chain including labor 600 baht.

Man ya gotta LOVE Thailand!!!

All top quality parts, no doubt

[sinewave]

I was running around alot today and am pegging 120kph much sooner and sustaining it without any problems, will do a full throttle test tomorrow. If alls well, may go back and experiment with a 14 tooth front.

140-150 kph was the top speed with the old 16/42 ratio.

16/47 as someone else also tried on this board, is also a 2.9 ratio (47/16) so should be the same, the new sprocket is a little bit thicker than the old one.

[sinewave]

much easier to lift the front wheel, 3rd gear im hitting 11k rpm alot easier, flies there, 0-60kph much stronger, punks out and floats at 60-80kph , then pulls hard from 80-120, another 6-7 seconds takes you to 140kph.

75 kilo rider

[PeaceBlondie]

Ah, to be 78 kg again...I do think that I will change to "lower" gearing soon. I do not need that last 10 kph anyway, and want the extra acceleration. Mileage is so good it cannot suffer much.

Are you saying the sprocket teeth are thicker? Sounds wrong.

[sinewave]

The new sprocket is thicker, but i cant guarantee the old sprocket was stock.

and you wont be losing any top speed, going from 120-140kph will just be a little louder, but the throatier tone sounds good. I made it past 140kph today.

Edited March 31, 2009 by sinewave

[PeaceBlondie]

The new sprocket is thicker, but i cant guarantee the old sprocket was stock.

and you wont be losing any top speed, going from 120-140kph will just be a little louder, but the throatier tone sounds good. I made it past 140kph today.

Sorry to disagree, but a simple gearing change that creates 10-15% more torque and louder exhaust at the same road speed will decrease your top speed. Simple mechanical fact, unless you rev it past 14,000 rpm

[sinewave]

Yes if you look at the numbers and do the math of course, but the CBR isnt losing topspeed with this gear change, it just rides a higher rpm and since the revolutions are higher it is stronger on top, since this engine likes higher rpms. The powerband which was subtle to non existent before, is now definately more pronounced.

Before the throttle would be pinned at 140kph, now I have about 10-15% left since the engine doesnt have to work so hard for the old 16/42 ratio. It rides the higher rpms which this engine likes to do.

I promise you will like it, the only downpoint is when you cruise slow in traffic in first gear and goose the throttle, the bike likes to jump from under you , peppy !

[sinewave]

150kph @ 10k rpm today with about a 5 kph front right crosswind, still more room to go on the throttle, but traffic was coming up.

whats the deal with the cutout, sometimes it cuts sometimes it doesnt.

[cbr125]

150kph @ 10k rpm today with about a 5 kph front right crosswind, still more room to go on the throttle, but traffic was coming up.

whats the deal with the cutout, sometimes it cuts sometimes it doesnt.

Awesome to read that it has so much powa´, i have a cbr125 2009, and this year i will put a 166cc on it

what sprocket would you recomend?

i will be happy with 140-145kmh on gps

Edited September 22, 2009 by cbr125

[OneeyedJohn]

The title (Cbr150 Sprocket Changed 15/44 from 16/42 ) of this thread is opposite to what you say

I went from a 16/42 to a 15/44 ratio

[13budgies]

Hi, everyone, I'm new here.

Sinwave, 15/44 is standard. It seems like you have gone from way overgeared (11-12% over standard) back to exactly how the bike came out of the factory.

But 150kph at 10,000? At the11500 redline that would give more than 170kph indicated. I don't think that's quite right! If I remember rightly my cbr,

on standard tyres, gave an indicated 130/135kph at 10500rpm.

What size tyres are you on?

Dave

[thomo]

The title (Cbr150 Sprocket Changed 15/44 from 16/42 ) of this thread is opposite to what you say

I went from a 16/42 to a 15/44 ratio

No it isn't.

from...

to...

I picked up a stock chain and sprockets last month, the cheapy was about 700b, the DID was 1,900. Went for the DID.

Half regret it though. Wouldn't mind having cheapies so I can play around with the sizes without wasting my 1,900b.

Edited July 27, 2010 by thomo

[Briggsy]

I know this is an old thread.

I have a 2010 new model CBR 150 R fuel injection

My stock factory chain reached the end of its life after 15,000 km. (not impressed by that, but that's another story)

After going round all the bike shops, I got the same story that I would need to order a new chain and sprocket set and it would be at least a week. Since I have to do heavy mileage between work sites, a week was pushing it. I waited a week and then was told I would need to wait another week.

I found a bike shop that claimed to have one but I was sure it was a non-standard part of some description due to the price, 550B + 200B for fitting it. They asked me if I wanted 44 or 45 teeth. I went for 44.

They fitted it (with a lot of hammering, didn't like that). The result is it works but a big loss of top end. At 6,000 rpm previously the bike did 85 km/h, now it does 74 km/h. That's a 13% loss of speed at equivalent rpm. That's too much for me. Thank God I didn't get a 45-tooth sprocket on the back.

Since they didn't give me the old sprockets back, can anyone tell me what the standard factory sprocket ratios are. That information is not in the manual.

I am going to change back to whatever it was.

[13budgies]

I know this is an old thread.

I have a 2010 new model CBR 150 R fuel injection

My stock factory chain reached the end of its life after 15,000 km. (not impressed by that, but that's another story)

After going round all the bike shops, I got the same story that I would need to order a new chain and sprocket set and it would be at least a week. Since I have to do heavy mileage between work sites, a week was pushing it. I waited a week and then was told I would need to wait another week.

I found a bike shop that claimed to have one but I was sure it was a non-standard part of some description due to the price, 550B + 200B for fitting it. They asked me if I wanted 44 or 45 teeth. I went for 44.

They fitted it (with a lot of hammering, didn't like that). The result is it works but a big loss of top end. At 6,000 rpm previously the bike did 85 km/h, now it does 74 km/h. That's a 13% loss of speed at equivalent rpm. That's too much for me. Thank God I didn't get a 45-tooth sprocket on the back.

Since they didn't give me the old sprockets back, can anyone tell me what the standard factory sprocket ratios are. That information is not in the manual.

I am going to change back to whatever it was.

Stock is 15/44, and 74km/h is about right for standard tyres. It seems you've gone from around 15% overgeared back to standard.

[KRS1]

Check how many teeth the front sprocket is, should be 15.

What was your previous ratio?

[kermitzkitchen]

I know this is an old thread.

I have a 2010 new model CBR 150 R fuel injection

My stock factory chain reached the end of its life after 15,000 km. (not impressed by that, but that's another story)

After going round all the bike shops, I got the same story that I would need to order a new chain and sprocket set and it would be at least a week. Since I have to do heavy mileage between work sites, a week was pushing it. I waited a week and then was told I would need to wait another week.

I found a bike shop that claimed to have one but I was sure it was a non-standard part of some description due to the price, 550B + 200B for fitting it. They asked me if I wanted 44 or 45 teeth. I went for 44.

They fitted it (with a lot of hammering, didn't like that). The result is it works but a big loss of top end. At 6,000 rpm previously the bike did 85 km/h, now it does 74 km/h. That's a 13% loss of speed at equivalent rpm. That's too much for me. Thank God I didn't get a 45-tooth sprocket on the back.

Since they didn't give me the old sprockets back, can anyone tell me what the standard factory sprocket ratios are. That information is not in the manual.

I am going to change back to whatever it was.

Stock is 15/44, and 74km/h is about right for standard tyres. It seems you've gone from around 15% overgeared back to standard.

If you were after the ratios for the FI model stock is 15/43

[13budgies]

I know this is an old thread.

I have a 2010 new model CBR 150 R fuel injection

My stock factory chain reached the end of its life after 15,000 km. (not impressed by that, but that's another story)

After going round all the bike shops, I got the same story that I would need to order a new chain and sprocket set and it would be at least a week. Since I have to do heavy mileage between work sites, a week was pushing it. I waited a week and then was told I would need to wait another week.

I found a bike shop that claimed to have one but I was sure it was a non-standard part of some description due to the price, 550B + 200B for fitting it. They asked me if I wanted 44 or 45 teeth. I went for 44.

They fitted it (with a lot of hammering, didn't like that). The result is it works but a big loss of top end. At 6,000 rpm previously the bike did 85 km/h, now it does 74 km/h. That's a 13% loss of speed at equivalent rpm. That's too much for me. Thank God I didn't get a 45-tooth sprocket on the back.

Since they didn't give me the old sprockets back, can anyone tell me what the standard factory sprocket ratios are. That information is not in the manual.

I am going to change back to whatever it was.

Stock is 15/44, and 74km/h is about right for standard tyres. It seems you've gone from around 15% overgeared back to standard.

If you were after the ratios for the FI model stock is 15/43

Sorry, I gave details for the old model probably because the thread was about the old model. Put it down to pre-senile dementia. On second thoughts, forget the pre-!

[Briggsy]

Got a 42 tooth back sprocket yesterday. It's almost back to how it was. It now does 81 km/h at 6,000 rpm. I suspect I now have a 14-tooth front. That would account for the difference. i.e. Gone from 15/43 to 14/44 to 14/42.

Thanks for the info anyhow.

[JeffreyMcCollum]

It's a math and numbers game only. The engine still is the same, so same power and same torque. Period

If you want to lift your front wheel easier and start off quicker, yes lower front and higher rear sprocket. However at a cost of top end and MPG km/L your just running at higher RPM in every gear.

On my CBR I added at front tooth, and removed 1 on the back. I do lots of cross country rides, and 500 - 600 km days on my CBR, some times 1 up some times 2 up. I wanted it easier on the motor (longer life) and higher fuel economy. I now get 46 km/l on the road.

If I need the extra power to pass I just drop a gear or two. And have what I need.

Did the same on my Ninja +2 teeth front. lowered RPM at crusing speed and MPG about the same as your getting on your CBR150

I a rider, not a stop light racer