cbr 250 ticking update

[KRS1]

ok so my bike developed a ticking sound and locked up for a split second doing 160 kph...

opened the valve cover today and snuck in a feeler gauge, the right intake shim has disintegrated, as in nothing there....exhaust shims were in spec (but on last 0.01 tolerance), intake was left side: 0.25...factory tolerance is 0.16 +/-0.03 ....its a bit over tolerance ...

couldnt even get a feeler under the right rocker arm, so a new rocker is needed...and its possible its going to require a new valve, or valve seats cut if the seats are too pitted.

at this point im trying to figure out how to calculate the size of the missing shim??? I think the thing to do is throw an old shim in there and calculate the thickness using an old shim, but what if the valve or seat is beyond just sticking a new shim in ? just going to have to try eh?

to top it off, as i was putting the valve cover back on, i overtightened and snapped the valve cover bolt, now i have to drop the engine like a fool and eazy-out the bolt stem...fun days ahead

[Overandout]

Just a thought here:

How close to the redline were you and for how long?

The reason I ask is that I once held a GPz 600R at 1k over the redline for a mile or so racing an FZR600. When I slowed down it was ticking like a cheap clock.

It turned out that the cams had started to bounce and all the cam journal bolts had stripped their threads, the only thing keeping the cams in was the chain! The surface of the rockers where the cams contact looked like corrugated roof sheeting!

If yours was the same on the inlet side, that might explain the huge differences in tolerances between one valve and the other.

I hope for your sake its not the case as I had to put a new head on the GPz.

Edited to add: It was worth it by the way, because I did stay in front of the FZR, and it was my ex-g/f riding the Yam!

Edited March 20, 2014 by Overandout

[BirdsandBooze]

Been there myself with the dropping something in the crankcase. If there`s much that needs doing it might be cheaper for you to source a new top end from a crasher rather than work on what you`ve got.

[KRS1]

Just a thought here:

How close to the redline were you and for how long?

The reason I ask is that I once held a GPz 600R at 1k over the redline for a mile or so racing an FZR600. When I slowed down it was ticking like a cheap clock.

It turned out that the cams had started to bounce and all the cam journal bolts had stripped their threads, the only thing keeping the cams in was the chain! The surface of the rockers where the cams contact looked like corrugated roof sheeting!

If yours was the same on the inlet side, that might explain the huge differences in tolerances between one valve and the other.

I hope for your sake its not the case as I had to put a new head on the GPz.

Edited to add: It was worth it by the way, because I did stay in front of the FZR, and it was my ex-g/f riding the Yam!

i think it was probably about 1.5k-2k away from redline, but it did feel like something wasnt right, but kept pushing...i wrote it off as headwind, atmospheric pressure, humidity etc...i also switched oil from Castrol Power 1 to Valvoline Syn speed around 1 kilometers ago (after using castrol for over 30k kilometers)....and could tell off the bat it wasnt as slippery as Castrol...im wondering if this had anything to do with it at all.

I have to take a look at a parts diagram and see what the part is that holds the shim in place, more than likely will have to replace that too, since the rocker has been beating on it without a shim.

btw, nothing fell in the motor yet, i just broke off the valve cover bolt within the bolt hole, but a cross member is in the way and i cant drill it out unless i drop/angle the engine.

[KRS1]

Been there myself with the dropping something in the crankcase. If there`s much that needs doing it might be cheaper for you to source a new top end from a crasher rather than work on what you`ve got.

good idea, things are never simple when parts (like a shim) go completely missing...lol

[T_Dog]

Gee, what has happened to Honda quality? I took my old 750F and 700SC to redline and beyond regularly for many years. Now I hear about this and the 500X bikes are losing oil? Honda used to be the standard for a long life bike.

[KRS1]

Gee, what has happened to Honda quality? I took my old 750F and 700SC to redline and beyond regularly for many years. Now I hear about this and the 500X bikes are losing oil? Honda used to be the standard for a long life bike.

ill admit my bike isnt stock, its derestricted in more ways than one. Without the derestrictions it probably would not have failed.

through in a new CCT 2 months ago before anyone brings that up ...and btw, i thought it was the CCT (again) at first, so replaced that yesterday...the CCT from a Honda Click fits and is 300 baht vs 550 baht for the standard CBR 250, its just a different color. Then tried the reed valve for the PAIR, wasnt it...then got the feeler out and cracked open the valve cover.

at this point dont know if im going to DIY or let the dealer handle it, now that i know what the problems are. Afraid of dealer rape.

Edited March 20, 2014 by KRS1

[speedtripler]

Gee, what has happened to Honda quality? I took my old 750F and 700SC to redline and beyond regularly for many years. Now I hear about this and the 500X bikes are losing oil? Honda used to be the standard for a long life bike.

their small bikes are still class leaders and havent heard of much p;roblems with the cbr 1000rr either

seems likee their mid size bikes have a few niggles to be worked out but im sure honda will sort it out

there not brand -x from china that will disappear of the face of the earh after they sell a handfull of bikes etc

[guzzi850m2]

Just a thought here:

How close to the redline were you and for how long?

The reason I ask is that I once held a GPz 600R at 1k over the redline for a mile or so racing an FZR600. When I slowed down it was ticking like a cheap clock.

It turned out that the cams had started to bounce and all the cam journal bolts had stripped their threads, the only thing keeping the cams in was the chain! The surface of the rockers where the cams contact looked like corrugated roof sheeting!

If yours was the same on the inlet side, that might explain the huge differences in tolerances between one valve and the other.

I hope for your sake its not the case as I had to put a new head on the GPz.

Edited to add: It was worth it by the way, because I did stay in front of the FZR, and it was my ex-g/f riding the Yam!

Now that was a funny story man, he-he.

[metisdead]

A rather unintelligent post has been removed as well as a flame post.

[BSJ]

Just a thought here:

How close to the redline were you and for how long?

The reason I ask is that I once held a GPz 600R at 1k over the redline for a mile or so racing an FZR600. When I slowed down it was ticking like a cheap clock.

It turned out that the cams had started to bounce and all the cam journal bolts had stripped their threads, the only thing keeping the cams in was the chain! The surface of the rockers where the cams contact looked like corrugated roof sheeting!

If yours was the same on the inlet side, that might explain the huge differences in tolerances between one valve and the other.

I hope for your sake its not the case as I had to put a new head on the GPz.

Edited to add: It was worth it by the way, because I did stay in front of the FZR, and it was my ex-g/f riding the Yam!

i think it was probably about 1.5k-2k away from redline, but it did feel like something wasnt right, but kept pushing...i wrote it off as headwind, atmospheric pressure, humidity etc...i also switched oil from Castrol Power 1 to Valvoline Syn speed around 1 kilometers ago (after using castrol for over 30k kilometers)....and could tell off the bat it wasnt as slippery as Castrol...im wondering if this had anything to do with it at all.

I have to take a look at a parts diagram and see what the part is that holds the shim in place, more than likely will have to replace that too, since the rocker has been beating on it without a shim.

btw, nothing fell in the motor yet, i just broke off the valve cover bolt within the bolt hole, but a cross member is in the way and i cant drill it out unless i drop/angle the engine.

I would steer clear of Valvoline. I think it's probably OK with old slow reving American V8's....but high revving engines no way.

I put Valvoline in a Mitsubishi once and it was rattly! After a couple of thousand k's I did another oil & filter change back to Castrol and it was back to smooth running!

[KRS1]

now the question is...where is the missing shim ?

[yankee99]

Why don't you just pull the head and see what's going or does the engine need removed for the head yo come off.

[ktm jeff]

I fear the missing shim is in fragments throughout your engines internals.Engine may want complete strip down and flush out of all oil journals.Smallest piece left in could wreck re-built engine.I would consider a rebuild to 300cc or another engine from a crashed bike.Good luck.

[KRS1]

Why don't you just pull the head and see what's going or does the engine need removed for the head yo come off.

i stopped by a shop and they suggested pulling the engine out...later i thought about it and wondered...<deleted>? is he talking about, just need to pull the head to get the broken bolt out. Im pretty sure you just have to remove the radiator to get the head out the front, i unmounted the radiator and pushed it down to get the valve cover off.

giving it to the dealer for this one, by the time i buy a micrometer, tuk tuk fare, and minus 2 weeks of fuel i wouldve burnt riding around, the cost is coming out to the same amount if i did it myself.

Plus theres too much running around involved, id have to install the new rocker (have to order) before i can take intake shim measurements for new shims (order again)

Mechanic i spoke to gave me a glimmer of hope and honesty though, i was going to get him to reseat the valves since the head had to come out, but he suggested that he check it first since the oem valve seats are better than cutting new ones and the original factory metallurgy is very hard and durable. I reseated a cbr 150 once and can verify that what he said was true. The factory has a double grind.

[KRS1]

I fear the missing shim is in fragments throughout your engines internals.Engine may want complete strip down and flush out of all oil journals.Smallest piece left in could wreck re-built engine.I would consider a rebuild to 300cc or another engine from a crashed bike.Good luck.

one of the fragments already got me at 160kph, hopefully it shattered.

Im going to stick a bunch of neodymium magnets under the case to get the chunks.

[Dave 74]

Gee, what has happened to Honda quality? I took my old 750F and 700SC to redline and beyond regularly for many years. Now I hear about this and the 500X bikes are losing oil? Honda used to be the standard for a long life bike.

These are Thai manufactured Hondas, not Japanese.

They are also built to be cheap and affordable, for newbs that don't really know bikes.

Perhaps therein lies your answer.

[yankee99]

I think that you are going about correctly although I would make sure to personally inspect the head and cylinder when its open.Being its Thai made parts should be available and cheap.

[KRS1]

dealer found the shim to the side of the valve springs. I think it got caught in the valve spring causing it to lock the bike up momentarily at 160kph. valve cover bolt hole retapped already.

they said the rocker is still good

but how did the shim get out ???

[transam]

OP, you will have to invest in a torque wrench.........

[KRS1]

OP, you will have to invest in a torque wrench.........

hope the dealer uses one !

ประแจแรงบิด = torque wrench (bra-ja-rang-bit)

[T_Dog]

dealer found the shim to the side of the valve springs. I think it got caught in the valve spring causing it to lock the bike up momentarily at 160kph. valve cover bolt hole retapped already.

they said the rocker is still good

but how did the shim get out ???

Those shims are retained pretty well, so I expect what you found was a manufacturing defect. It was intended to be placed on the pin, but it flipped out before everything else came together. Does that make sense? Really good that you found it in there rather than never knowing what oil channel it was going to plug up.

[paz]

Most work can be done w/o a torque wrench.

The easier tecnique is to keep the spanner with one or two fingers only at a short distance from the bolt head. Once rotations stop give an one eight, or quarter turn more, depending on bolt size.

In reality with a little training once can get pretty close to exact value, it's just a matter of developing the sensibility and using common sense.

[yankee99]

Most work can be done w/o a torque wrench.

The easier tecnique is to keep the spanner with one or two fingers only at a short distance from the bolt head. Once rotations stop give an one eight, or quarter turn more, depending on bolt size.

In reality with a little training once can get pretty close to exact value, it's just a matter of developing the sensibility and using common sense.

This is true for many not critical thing but in general bad advice. Things that need to seat evenly to prevent leakage and maintain a flat surface can not be done in steps without a torque wrench. Why anyone would take a chance of doing double work for a small investment is beyond me.

[paz]

Most work can be done w/o a torque wrench.

The easier tecnique is to keep the spanner with one or two fingers only at a short distance from the bolt head. Once rotations stop give an one eight, or quarter turn more, depending on bolt size.

In reality with a little training once can get pretty close to exact value, it's just a matter of developing the sensibility and using common sense.

This is true for many not critical thing but in general bad advice. Things that need to seat evenly to prevent leakage and maintain a flat surface can not be done in steps without a torque wrench. Why anyone would take a chance of doing double work for a small investment is beyond me.

First of all a quality torque wrench is not small investment, and to cover small and large bolts, at least two are needed.

Then, a bolt or nut tightened to the wrong torque still creates a flat surface contact. But excessive tightening can of course cause materials distorsion and breakage.

As a practice one shuld use torque wrench on structural engine bolts eg cams connecting rods etc, and learn hand tightening for the rest.

[KRS1]

Hopefully they wont use sticky rice to hold everything in place.

Now the long painful wait to order shim sizes. Already going through bike withdrawl..

Looking at pistons now that im bikeless and bored, seems JE piston has a 300cc piston 7mm oversize, would have to get a barrel made and Power Commander...heh..but maybe it would be better to do it to the new 300 cbr and turn it into a 350

[KRS1]

Most work can be done w/o a torque wrench.

The easier tecnique is to keep the spanner with one or two fingers only at a short distance from the bolt head. Once rotations stop give an one eight, or quarter turn more, depending on bolt size.

In reality with a little training once can get pretty close to exact value, it's just a matter of developing the sensibility and using common sense.

This is true for many not critical thing but in general bad advice. Things that need to seat evenly to prevent leakage and maintain a flat surface can not be done in steps without a torque wrench. Why anyone would take a chance of doing double work for a small investment is beyond me.

First of all a quality torque wrench is not small investment, and to cover small and large bolts, at least two are needed.

Then, a bolt or nut tightened to the wrong torque still creates a flat surface contact. But excessive tightening can of course cause materials distorsion and breakage.

As a practice one shuld use torque wrench on structural engine bolts eg cams connecting rods etc, and learn hand tightening for the rest.

hard to do hand torqueing on the cbr 250 valve cover bolt, theres a rubber washer underneath the bolt head...couldnt really tell when it was tight because of the rubber, i had to use a long ass extension too, so it was even harder to tell when it was tightened - then snap free spin, i hate when that happens.

[yankee99]

Hopefully they wont use sticky rice to hold everything in place.

Now the long painful wait to order shim sizes. Already going through bike withdrawl..

Looking at pistons now that im bikeless and bored, seems JE piston has a 300cc piston 7mm oversize, would have to get a barrel made and Power Commander...heh..but maybe it would be better to do it to the new 300 cbr and turn it into a 350

Shim kits are readily available so unless your bike does not use common shims I would assume they should be able to squire them quickly.

[transam]

Most work can be done w/o a torque wrench.

The easier tecnique is to keep the spanner with one or two fingers only at a short distance from the bolt head. Once rotations stop give an one eight, or quarter turn more, depending on bolt size.

In reality with a little training once can get pretty close to exact value, it's just a matter of developing the sensibility and using common sense.

This is true for many not critical thing but in general bad advice. Things that need to seat evenly to prevent leakage and maintain a flat surface can not be done in steps without a torque wrench. Why anyone would take a chance of doing double work for a small investment is beyond me.

First of all a quality torque wrench is not small investment, and to cover small and large bolts, at least two are needed.

Then, a bolt or nut tightened to the wrong torque still creates a flat surface contact. But excessive tightening can of course cause materials distorsion and breakage.

As a practice one shuld use torque wrench on structural engine bolts eg cams connecting rods etc, and learn hand tightening for the rest.

hard to do hand torqueing on the cbr 250 valve cover bolt, theres a rubber washer underneath the bolt head...couldnt really tell when it was tight because of the rubber, i had to use a long ass extension too, so it was even harder to tell when it was tightened - then snap free spin, i hate when that happens.

If you have a rubber washer the torque setting will be a little over hand tight.

[KRS1]

Hopefully they wont use sticky rice to hold everything in place.

Now the long painful wait to order shim sizes. Already going through bike withdrawl..

Looking at pistons now that im bikeless and bored, seems JE piston has a 300cc piston 7mm oversize, would have to get a barrel made and Power Commander...heh..but maybe it would be better to do it to the new 300 cbr and turn it into a 350

Shim kits are readily available so unless your bike does not use common shims I would assume they should be able to squire them quickly.

i can get them if i go to the larger honda parts dealer in cnx, but i went to another dealer and protocol is parts from their franchises only ... unfortunately.

i even tried to bribe the mechanic...lol