Engine Transplant TDM 900 will it fit?

[trixi]

Hi there everybody. This may have been covered to death already.But i'm new here so maybe i just need pointing to the right page. Does anyone have any info about shoving a TDM 900 fuel injected 6 speed motor into a TRX850 . I have a 1997 TRX. it's low mileage and well pampered. But the nasty Yamaha "breaking sticks with your foot" gearbox is playing up. Keeps trying to jump out of 2nd when you wind it on. I cant see the cost of tearing it down to get the dogs undercut/and /or replacing the gear-set + relevant selector fork will be much less than buying a TDM motor, with what i understand to be a much improved gearbox.Bearing in mind i would have to split the cases on the TRX motor, and to do that you have to remove the top end . So i would need a complete set of gaskets and "O" rings etc. I priced it at my local dealer and it was a shocker!! Unless any one has a fix for the gearbox?? I have had experience with this type of thing before(on an EXUP) and there was not a get around. You just had to stump up for the parts or freewheel to the pub!!

[kingoffifa]

http://trx850.motomaniac.net/forum/sear ... mit=Search

you will get given out to - you better use the search function - otherwise the people who know the answer to your question will inform you that you should use the search function

my search tips - if you are looking for something quite specific - like tdm 900 search the first post for the key term you are looking for.

if the term is more generic - front fork - then use the post heading as a search area

[Killerwhale]

Hi there everybody. This may have been covered to death already.But i'm new here so maybe i just need pointing to the right page. Does anyone have any info about shoving a TDM 900 fuel injected 6 speed motor into a TRX850 . I have a 1997 TRX. it's low mileage and well pampered. But the nasty Yamaha "breaking sticks with your foot" gearbox is playing up. Keeps trying to jump out of 2nd when you wind it on. I cant see the cost of tearing it down to get the dogs undercut/and /or replacing the gear-set + relevant selector fork will be much less than buying a TDM motor, with what i understand to be a much improved gearbox.Bearing in mind i would have to split the cases on the TRX motor, and to do that you have to remove the top end . So i would need a complete set of gaskets and "O" rings etc. I priced it at my local dealer and it was a shocker!! Unless any one has a fix for the gearbox?? I have had experience with this type of thing before(on an EXUP) and there was not a get around. You just had to stump up for the parts or freewheel to the pub!!

I´m doing it now...
You change: oiltank (need rework OR adapterplate), oiltray, stator+flywheel+generatorcover...you move TRX head/cams/carbs....special made front sprocket(and cut off speedo)...move rear sprock 6mm out on a YZF swinger...i think 10 on standard.

OR you only do oiltank/tray and move the harness but then you will need to make a bracket on the left side of the 900 head to fit in the TRX frame. Right side has a mounting point but it´s not drilled out...

Probably forgetting something....but in general. That´s it.

[trixi]

Thanks for getting back to me on that. I have used the search button to quite good effect. Thanks for the tips. Disappointed not to find some kind of step by step guide. But that's 'cos i am lazy i guess!! My choice is either to just out my TRX complete with its slightly iffy 2nd gear, or fix it, or replace the motor. Now i don't see many comments about the gearbox on these bikes. But i am non to pleased with the one i got. My bike is low milage well looked after and uses no oil.But the box has always been a bit random. My main reason for thinking about stuffing a TDM motor in is to get a better gearbox. I always thought that the TRX could have done with 6 speeds anyway. But i come from a background of hi-revving fours and I'm just used to having six. I don't think the power spread on a TRX is really good enough to get away with 5 . But it depends on the roads you have to use it on to a degree. I'm now living in West Australia. And in between dodging the 4wd's, potholes and radar traps there's a bit of a premium on enjoying a bike like a TRX out here. I just keep thinking about how much fun it would have been to ride on the French "A" roads me and my mates used to terrorise in the last century before i moved out to the lucky country!!

[Killerwhale]

Thanks for getting back to me on that. I have used the search button to quite good effect. Thanks for the tips. Disappointed not to find some kind of step by step guide. But that's 'cos i am lazy i guess!! My choice is either to just out my TRX complete with its slightly iffy 2nd gear, or fix it, or replace the motor. Now i don't see many comments about the gearbox on these bikes. But i am non to pleased with the one i got. My bike is low milage well looked after and uses no oil.But the box has always been a bit random. My main reason for thinking about stuffing a TDM motor in is to get a better gearbox. I always thought that the TRX could have done with 6 speeds anyway. But i come from a background of hi-revving fours and I'm just used to having six. I don't think the power spread on a TRX is really good enough to get away with 5 . But it depends on the roads you have to use it on to a degree. I'm now living in West Australia. And in between dodging the 4wd's, potholes and radar traps there's a bit of a premium on enjoying a bike like a TRX out here. I just keep thinking about how much fun it would have been to ride on the French "A" roads me and my mates used to terrorise in the last century before i moved out to the lucky country!!

"use no oil" - MUST be something wrong with your TRX mate!!
Spoke to a dude who tuned his TDM900 a bit, higher comp wiseco´s...hotter cams & stiffer valvesprings and it made 96hp. That´s +10hp....not bad! I´m going to do more trackday´s next year and there are a nice slipper clutch out there for the tedium. I think i will have a TRX how it should be....although i would like to see Yamaha put the 1200 enjun in a TRX!

[Mincehead]

Slipper clutch? You`ve got a lever to play with KW, manipulation of the clutch lever does the same thing and it`s so much cheaper too!
It`s worked fine for racers for the last half century or more, many racing greats have played the old clutch lever `tune` to great effect.

[sandmacker]

Yamaha came up with a 6 speed close ratio racing gearbox , but they were very expensive . $5,000 I think . Seems like alot of work for one cog though . There's a turbo'd Trixie about somewhere . Packed about 130kw I think . Might be worth a look into that