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-   -   replacing my 5th gear again! (https://www.horizonsunlimited.com/hubb/yamaha-tech/replacing-my-5th-gear-again-46417)

jim 12 Nov 2009 07:39

replacing my 5th gear again!
 
I think we're all pretty much familiar now with the 5th gear story on the 34L- I was not a believer until I opened up my bike 5 years ago in preparation for a trans Africa trip, but I replaced the 5th gear and it's mate and rode accross Africa twice always considerate of the fact that these bikes dont like low rev riding in 4th and 5th and thought then that such troubles were over. I was wrong. Ive opened the old beast up again now to find that the "new" 5th gear as well as the old 4th need replacement! F**ck!
Anyways Ijust thought Id share that in case anyone thinks, like I did, that their 5th gear troubles were over.:nono:

G600 12 Nov 2009 11:27

Thanks for sharing.

How many KM do you have on the gears you are now changing?

Can you post pictures of the gears?

jim 12 Nov 2009 15:54

5th Gear Photos
 
I have photos I can send you but I dont know how to attach them on here.... I can email them to you.
The current 5th gear has about 35000km on it, but 35000km of riding by someone who was constantly aware of the 5th gear issue and so made a point of being careful not to ride in 5th below 3500rpm (as much as is possible on bad roads). The 4th gear is on 79 000km , when i replaced the 5th originally (at around 45000km) I saw that the 4th was not 100% but it looked good enough and I couldnt afford it then so I left it be. Incidentally Im also having to replace my oil pump, various seals and doing a top end overhaul.

Jim

guzzibob 12 Nov 2009 18:19

Gear worries
 
Scary stuff! Having recently bought an 86 1VJ with 29000km on the clock, I'm now thinking I ought to take a look inside the gearbox! Is there any way I can get an indication of gear condition without stripping, eg backlash through the final drive sprocket, metal in the oil, noise etc? I'm not frightened of splitting the cases etc (honest!), but would just rather avoid it! BTW, anyone got experience of what the final failure mode is - ie do you just lose the top 2 gears, and can go on with 3?

kenymact 12 Nov 2009 19:34

Hi,I just bought a 2002 and the fifth gear sounds bad,how easy it to replace the gears and do I need a full gasket set?I may as well check the piston out as I need to take the top off too ,I was hoping to get through the summer but I don,t know how long 5th will last....

Bobmech 12 Nov 2009 22:20

Keny, how many km on yours?
Do a search here on "5th gear" & you'll find plenty of info incl upgraded oil pumps, etc for the early models to help with 5th gear wear.
Bob

jim 13 Nov 2009 07:40

As far as I know the 5th gear problem is unique to the 34L Tenere which was the first one Yamaha made so later models came out with an improved gear. You can tell (sometimes) that the gear is going if you ride in 5th close to a wall or barrier and you can hear a sortof deep humming sound echo off the wall... Vague I know, but basically it seems that if you are riding a 34l with around 40000km on the clock it more than likely needs attention. Unfortunatley checking the gears does require a full strip down of the crank case which is a pretty big job. I would recommend that if you do go for it you use the opportunity to replace the big ends and any other bearings or seals that look even remotely suspicious (bearings and seals need not be bought from Yamaha- you can get perfectly good ones for a fraction of the cost from an engineering supplier). Of course also all gaskets will need replacing and hell you may as well do the top end too! Also to replce the actual gear you need a press to remove and replace the gears from their shaft- I have it done by an engineering workshop, there are clearance limits listed in the Clymer Manual for this job. The crank case halves dont have a gasket, they just take a bit of sealer. BTW no oil pump upgrade will have any effect on your gears. As for what happens when the gears do finally go- I would imagine that it could be disasterous and result in a totally mangled engine as there would be lots of little pieces of metal in the gearbox and oil pump... ugly.

guzzibob 13 Nov 2009 14:24

Thanks for that Jim. Think I'll risk leaving it unchecked for next years Morocco trip, but will have to seriously consider getting stuck in if (when!) I manage to get my act together for a longer trip.

kenymact 13 Nov 2009 23:38

Hi Bob,mine has 74,000 kms on it and has a bad whine,don,t know how long it will last but maybe I can get a replacement engine cheap or wait till the winter and tear it down,I,ve asked a couple of questions on a local bike site and maybe I can find some one with a bit of experiance to help me do it.....know any where that is good for cheap gasket sets or parts .....cheers

G600 14 Nov 2009 19:09

Some pics from Jim...


http://i697.photobucket.com/albums/v...im_gear_01.jpg

http://i697.photobucket.com/albums/v...im_gear_02.jpg

Tenere Tom 14 Nov 2009 19:57

They look terrible!!!:thumbdown:

I've got a gear set in my shed that are immaculate in comparison!

It's a shame you are so far away!!!:(

kenymact 15 Nov 2009 02:36

I,d be willing to post or have a cash transfer to cover any costs if your still keen to help....ch:thumbup1:rs

MARK.F 15 Nov 2009 10:37

Here's what my 43F gearbox looked like:stormy:.
I only looked at it because the top end needed rebuilding...
http://i631.photobucket.com/albums/u...-Gears-WEB.jpg

G600 15 Nov 2009 11:19

Wow. Is that fifth and third? And fourth gear OK? Strange…

Do you know if your 43F has the same engine as Jim’s 34L?

This fifth gear thing seems pretty common.

Regarding what XT600 models are at risk, has someone experienced this fifth gear problem on a “newer” bike, say after 1990?

Pigford 15 Nov 2009 11:21

Hey G600, (spit it out)......................... or even a 2004/5 TTR600 !!!!!!!!


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