Broken my gears :-(

[AdamFZ]

Broken my gears | Strip down begun | WARNING Lots of Engine Porn !

Quick story to explain what happened....

Following traffic in 4th gear which suddenly stops. I forgot to shift down and am stuck in 4th gear. The traffic started moving again when i realized i was still in 4th and not moving very quickly. I dropped it down a gear or at least i thought i did and released the clutch and revved the engine but it seems it wasn't in any gear. I started rushing and panicking a little so i hit the down shift without the clutch unfortunately with the rev's still quiet high (5-8k) and BANG, i went into 3rd, wheel spun and away i went. This all happened in about 5-10 seconds.

Now there is a horrible grinding noise on load and lift off in 2nd gear !

What do peeps reckon I've done ?

I'm going to look into removing the gears in the coming days, anyone ever done this ?

Cheers,
Adam

 

[Gelvatron]

Drain the oil Check for metals in the oil maybe chunks of gear, does it shift when off on the center stand?

 

[Motogiro]

Do not run the bike anymore the gearbox and crank case share the same environment. Continued use will cause more damage

 

[AdamFZ]

Drain the oil Check for metals in the oil maybe chunks of gear, does it shift when off on the center stand?

Shifts fine... no issues there.

 

[Nelly]

Shifts fine... no issues there.

Seriously, you need to drain the oil and look for debris, The engine is pretty bullet proof but better safe than sorry,

Post up your results,

Neil

 

[BamBam]

Drain the oil Check for metals in the oil maybe chunks of gear, does it shift when off on the center stand?

second that.

any clunking/grinding under those circumstances is NOT good! I'm going to guess when you dropped it another gear without the clutch at a high RPM it caught the gear too fast and ripped something in the crankcase...

 

[AdamFZ]

Unfortunately i didn't realize the extent of the noise or damage done until i got into London so traveled approx 20 miles like that (not using 2nd gear but 4th, 5th and 6th)

I will be getting a recovery truck home tomorrow.

Cheers
Adam

 

[TownsendsFJR1300]

Unfortunately i didn't realize the extent of the noise or damage done until i got into London so traveled approx 20 miles like that (not using 2nd gear but 4th, 5th and 6th)

I will be getting a recovery truck home tomorrow.

Cheers
Adam

If you look at a picture of the transmission from either a shop manual or parts fisch, I suspect you probably knocked some cogs off (or seriously damaged them) one or two transmission gears, second gear or the idler gear most likely, of possibly knocked off some gear teeth. Doesn't really matter as the transmission needs to come out for a close look at. You won't know until the case is split.

Parts fisch: Yamaha Motorcycle Parts 2005 FZ6 - FZ6ST TRANSMISSION Diagram You can see the three small tabs (cogs) that stick out on the gear adjacent to the second gear. Second gear is part #20, the adjacent cogged gear is #23.

It is a big job, however someone on the forum did tear the engine down fully. Do a search. if you did it the way yamaha wants it done, it'll likely take longer to do. There's short cuts to everything. I'm 99% sure the cases have to be split, I do know the one shaft (with gears) has to come out the side of the engine(left side)

The shop I get my tires from had an R6 engine on the bench upside down with the pan off. The owner blew up the clutch and the friction plates got jambed up in the teeth of the gears and had to be hand picked out. (the owner couldn't afford a full tear down- the right way to do to find EVERYTHING).

 

[AdamFZ]

I did find these pictures of a R6 engine rebuild.... https://plus.google.com/photos/114258258571800441805/albums/5154166965616954081?banner=pwa

 

[SweaterDude]

Quick story to explain what happened....

Following traffic in 4th gear which suddenly stops. I forgot to shift down and am stuck in 4th gear. The traffic started moving again when i realized i was still in 4th and not moving very quickly. I dropped it down a gear or at least i thought i did and released the clutch and revved the engine but it seems it wasn't in any gear. I started rushing and panicking a little so i hit the down shift without the clutch unfortunately with the rev's still quiet high (5-8k) and BANG, i went into 3rd, wheel spun and away i went. This all happened in about 5-10 seconds.

Now there is a horrible grinding noise on load and lift off in 2nd gear !

What do peeps reckon I've done ?

I'm going to look into removing the gears in the coming days, anyone ever done this ?

Cheers,
Adam

you hit a false neutral and revved it to high (to much of a difference really) normally the transition in the rev's is taken up in the clutch but since you were in a false neutral with the clutch out, the gear(s) took the extent of the force.

 

[FinalImpact]

^^ I found those a couple years ago!!

http://www.600riders.com/forum/gara...ke-guts-heres-bunch-r6-engine-trans-pics.html


So - it only makes noise in 2nd gear all gears? A lot of detail would help. Franky the fact that the tire spun is a good thing. I can't believe it went in at those Rev's! You could pull the exhaust and pan but I'd like some detail on what it does right now from cold start to hot. Anything heavy that isn't in the pans bottom isn't going anywhere so I wouldn't be to worried about that.

 

[AdamFZ]

Noise is only in 2nd gear.... Rest of the gears are normal. Its not a constant grinding noise, it comes and goes and gets faster as i go faster. It's like a couple of teeth have sheered off on 2nd.

I'm going to pull the exhaust and oil pan tomorrow hopefully to have a ganders.

Cheers,
Adam

 

[FinalImpact]

You might PM ChevyFazer and ask him if you can see anything from looking up. It may just be some oil drain back holes and no real visible shots of the gear train.

These are constant mesh boxes, so the damage is likely to a clutch-dog (on the gear) or the slider where it engages.

See Pic:
Blue arrow on the right (clutch dog) fits into the recess on the left (slider) when that gear is selected. I'm guess it created a larger burr on the clutch dog, such that when that gear is not selected, the two parts are rubbing - but its ALL JUST SPECULATION on my part.

 

[TownsendsFJR1300]

That's pretty much what I posted in #8 less close up pic's. With the staggered gearcase, I don't believe you'll see much from below (but some small parts of 2nd gear) but may very well see a bit more from the top cover:

Yamaha Motorcycle Parts 2005 FZ6 - FZ6ST CRANKCASE Diagram .

Part #22 (cover) seems to allow you to look at a good part of the transmission, probably not all of it, especially as second gear is way over on the right. The cog that inserts into it may very well be visable.

Its highly un-likely you stripped all the teeth on one gear, the cog ends being ground down some/ rounded off, the holes they engage on the other gear, is where I'd put my oney if I was betting.

You won't know till you start a peeking.

Good luck...

 

[AdamFZ]

Thanks for all your replies.

I will post pics of my progress.

I'm not sure how much a 1996 YZF600 engine differs from ours but when he removed the oil pan, you can clearly see the gears.... [ame=http://www.youtube.com/watch?v=1Tdo8rFeBgg]YZF600 Engine disassembly 2nd Gear Rebuild, Full tear down. - YouTube[/ame]

Cheers,
Adam

 

[TownsendsFJR1300]

There's quite a bit of a difference just looking at the older engine than the FZ6, ie, cam chain in the middle of the engine, water pump much different, valve cover much different. Hopefully the transmission is closer to the same as the newer bike.

The post Randy put up with the links and pic's should be a big help. Looking closer at the shop manual, it appears none of the gears are pressed on the shafts like the old days..

Should dissassembly be needed, it appears you can leave the head on, pistons in, crankshaft in, flip the engine upside down and get to it after removing the clutch..


What ever you can't find or figure out in the shop manual, look up in the parts fisch, its extremly helpful:

http://www.partzilla.com/parts/search/Yamaha/Motorcycle/2005/FZ6+-+FZ6ST/parts.html

 

[Wh0M3]

I always try to get into first when I'm stopped. If I didn't stop in first or while down shifting I always try to get it back to first. I usually do it with a down shift, let out the clutch a little then repeat till I see the neutral light flash. I let the clutch out to make it move a bit so it is easier to down shift.

Sorry to hear about your issue, I hope that it isn't all that expensive for you to fix or get fixed.

 

[FinalImpact]

You might PM ChevyFazer and ask him if you can see anything from looking up. It may just be some oil drain back holes and no real visible shots of the gear train.

These are constant mesh boxes, so the damage is likely to a clutch-dog (on the gear) or the slider where it engages.

See Pic:
Blue arrow on the right (clutch dog) fits into the recess on the left (slider) when that gear is selected. I'm guess it created a larger burr on the clutch dog, such that when that gear is not selected, the two parts are rubbing - but its ALL JUST SPECULATION on my part.

Ya, so when we miss those shifts and/or hear that BIG CLUNK when dropped into low gear - those dogs ramming home is that noise! Thank god for metallurgists! Those straight cut gears are noisy and strong.

You might just pull the linkage from the left side of the top case and make sure all is well before dropping the whole thing from the frame. If you choose to do this yourself, its very doable. The hardest part stopping motion to remove nuts which can be done in the chassis with the chain and rear brake on. Beyond that a couple of pullers and you're in.

 

[TownsendsFJR1300]

You might just pull the linkage from the left side of the top case and make sure all is well before dropping the whole thing from the frame. If you choose to do this yourself, its very doable. The hardest part stopping motion to remove nuts which can be done in the chassis with the chain and rear brake on. Beyond that a couple of pullers and you're in.

There's at least one (from what I can see) shift dog on a gear on that shaft (that removes from the side). I don't believe, between the shift dog, and the other gears, FROM THE OTHER SHAFT meshing, that it'll pull out without the cases being split.

The gear (just to the right of your verticle blue arrow) is obviously where the shifter dog rides. That gear, the smooth shifter dog area and adjacent gear to the right appears to be one gear with cogs on the other side of it as well, its just engaged to the right...

**I am very cusrious as to what can be seen if that top cover (right above the transmission, 4 bolts) is removed..

At least the top end doesn't have to come off and nothing is pressed on the shafts...

Great project to do (especially if it isn't my engine), someone doing this the first time will learn alot...

Even if you pulled the motor yourself and had a shop fix the engine, that'd save probably half the labor costs...

 

[TownsendsFJR1300]

Ya, so when we miss those shifts and/or hear that BIG CLUNK when dropped into low gear - those dogs ramming home is that noise! Thank god for metallurgists! Those straight cut gears are noisy and strong.

.

That's part of the reason I have my idle set at 1,000 RPM's vs 1,300 and also hold the clutch in for a couple of seconds before shifting into first. It gives the transmission a chance to slow down a little before its in gear.

Actually, my driveway has some dowward tilt to it, so when starting out cold, I literally roll down hill about 20', then shift into first (especially with the cold engine oil).