TDM900 Engine conversion?

[cheap_trix]

John M wrote

I recently changed from Motul 5100 to Castrol Synth S and it seems that consumption has reduced, so oil choice appears to be a factor too.

Motul just introduced a new synthetic. 7100 20w50.

in the press blurb it is claimed to reduce misting and oil usage in large twins.
http://us.st11.yimg.com/us.st.yimg.com/ ... 6_26530872

[Max]

Yeah, that's what's in my bike right now. It's also supposed to be manufactured similar to the 300V (Racing) stuff.

[dandywarhol]

JPe, the bearing the question i asked re oil consumption between the trx and tdm, was that the main difference being compression ie i understand that the trx has higher compression.
so logically i was wondering if that was the case, if i were to raise the compression on the 900 would it start using oil like a 2 stroke!!

10.5 : 1 for the TRX and 10.4 : 1 for the 900.........less than 1%.....nah!

[barnarda]

I've looked into the TDM conversion and the TRX with TDM 900 barrels. The only benefit i can see from the TDM motor is 6th gear. The TDM 900 barrels with trx head as i have been told is possible but gives you less compression than a standard TRX. You can bore them out to 960 but that makes the engine really lumpy. As others have said by the time you've finished you'll have spent £1400. Thats about what light weight wheels would cost and the wheels will give you better gains than the engine.

There was an article in an old copy of performance bikes where they managed to fit a 6th gear to the TRX from a YZF 750. Unfortunately the guy left the mag and no one seams to be able to find him. I haven't given up on this up yet so if anyone out there has any new leads give me a shout.

Since having mine over-bored to 879cc the oil problem has gone as the TTS kit is very tight. Just had mine measured at 103bhp. But then I've spent £1000s mucking around with every part of it, and it doesn't look like it'll end soon as i want wheels and carbon fairing for xmas (big hope, one day maybe). I doubt if many TRX purists would approve. However it does often make newer bikes and born again riders look foolish.

[devlin]

Still has the soul of a TRX so go for it I reckon. I'll be slipping forks from one of the late model Japanese bikes, probably not R1 either. It is still a TRX.

[barnarda]

I went for exup ru as it was easy. besides all singing all dancing suspension is wasted on most of us, even those who aren't prepared to admit it. we're just not that good.
I believe that mine is still a TRX cause the engine is. and i have only ever out Yamaha stuff on. Well that's my justification. besides i bet even Frankenstein had a mother that loved him.

[devlin]

besides all singing all dancing suspension is wasted on most of us, even those who aren't prepared to admit it. we're just not that good.

We may never make full use of it but I know if it's well set up and works as good as it's going to get, it will give me a safer bike with heaps more margin between what I can do and the limits. Besides it's fun to have something different that you put together yourself.

[Kayla]

besides all singing all dancing suspension is wasted on most of us, even those who aren't prepared to admit it. we're just not that good.

We may never make full use of it but I know if it's well set up and works as good as it's going to get, it will give me a safer bike with heaps more margin between what I can do and the limits. Besides it's fun to have something different that you put together yourself.

I agree with this completely. I was finding the limits of the standard (Japanese) forks on my bike so swapped them for Thundercat, then Thunderace ones. With a new-ish R6 shock in as well it's loads better than it was (and way better now than I will ever be!) I do like to keep it Yam though

[SDN]

That's part of the point isn't it. I quite like the idea of changing the TRX by using parts that Yamaha had at the time and making a far better looking / performing bike. Make the TRX the bike it really should have been. As well as having a really unusual bike that people scratch their heads at and keep asking - " what the hell is that" in a good way. Also keeps us out of the pub!

[Quan-Time]

The oil consumption on the TRX is higher because of ring / piston design. thats all. It works MUCH better under load tho. Also the TDM has a Nikasil coating to aid the ring / piston shape change.
The TDM piston is LIGHTER and bigger than the TRX varient. And no, they are not interchangable. You would also need the conrod as the wrist / gudgeon pin is 20mm for TRX, and 22mm for TDM.

As for the TDM into a TRX. Yes its possible, but as many said, unless you can get a REALLY cheap complete bike, fit everything you need, then sell off all spare parts from the carcus, its not really worth it.

[dandywarhol]

IMO the oil consumption is greatly reduced on the 900 because of the use of a nikasiled/ceramic plated bore - that way the piston/cylinder clearance can be reduced dramatically as they expand at similar rates - from memory the clearance is about 30% of the TRX steel liner/piston clearance.

In a 5000 mile Euro trip my TDM900 used about less than 0.5 l of oil

[Russ]

I've got an Egli frame that needs a heart. A TDM 900 transplant seems like a good idea!
Anyone heard of transplanting TRX or TDM engines into a traditional type frame?

[Mincehead]

Oooo you rotter! Egli frames are as rare second hand as used condoms, not that you would want one.
Loads of room in Egli frames, I don`t see any problem beyond getting things all square and aligned, engine plates made up etc. Would love to see piccies once it`s done too.

[rbaron25]

... has anyone thought of getting together all of Mincehead's comments.. sayings.. on here and putting them into a coffee book... we could make a fortune, methinks.

Be interest if anyone has compared oil consumption per ml based on the Motul 5100 Motul 7100 and Castrol Synth S.
I have been keeping a mini diary on the use of Motul 5100 at the minute...

[Mincehead]

Not to my knowledge, does it matter?
Fresh oil continually going in is never a bad thing anyway, oil consumption shouldn`t be excessive unless you`ve got some serious wear issues in the motor.
If folk didn`t keep doing away with their underseat storage they could carry their spare oil around with them! By the way, I don`t particularly like coffee, I also write poetry sometimes, you could put that in the book along with my rantings, never know there could be a market for it.