Yamaha TRX850 Enthusiasts Forum

nice work. I like the look of your dash setup, but I agree - my dad had one and its very small.

Good to see you are still developing the bike

cobbadiggabuddyblooo wrote:From memory the sprocket side rear spacer will give about 1-2mm clearance from the centre raised section of the sprocket carrier but you need to remove the sprocket attachment stubs and machine down 6mm raised section flush to get your sprocket alignment.
Then the world is your oyster to do as you choose on the brake side.

Seems like a viable option, thanks!

coxylaad wrote:nice work. I like the look of your dash setup, but I agree - my dad had one and its very small.

Good to see you are still developing the bike

It's very...umm.. minimalistic?

At least the thing I really need and use works: The shiftlight. Honestly the rest is basically there to keep a rough track of the mileage.

It's slow going, but track season's over now so have put it up on the bench again. Planning on tearing the engine down while I still have temperature in the garage.

jpe70 wrote:

trixynut wrote:

but I did gain 500 grams in weight.

...and the extra weight added by the bigger tyre and longer chain is...

Naught. It's 900 grams lighter than stock... Oh, minus guesstimated 100 grams for the two new links in the chain.

Stock rear wheel with 160-tyre: 13,4 kilo
R6 rear wheel with 180-tyre: 12,5 kilo

I really appreciate the length of detail.Are all R6 wheels good for this swap, and was it a strait swap onto OEM swingarm? I'm curious if cog alignments are true between R6 and TRX.

mikethefish wrote:I really appreciate the length of detail.Are all R6 wheels good for this swap,

At least up to -08, they use different size brake disc from 05 or 06. 5-spoke are the lighter ones, early 3-spoke R6 matches TRX stock but with wider 5,5" rear.

mikethefish wrote:and was it a strait swap onto OEM swingarm? I'm curious if cog alignments are true between R6 and TRX.

No, different size axle and different offset of brake disc. Chain alignment are off by 6 mm. I use ThunderAce swingarm with a mix of R6 and R1 parts and a spacer behind front sprocket.

There are good writeups on R6 wheels in OEM swingarm on the forum.

F*ck... Wonder when this happened, noticed when I got back to garage first time after unloading after last trackday.



No more flasher mount holes.

That must have been a serious impact, how can you not notice this?
Maybe during transport something fell over on the tank?

Interesting stuff,

I'm following this post as I am also building a racebike.

Cheers.
Skelly.

Tarwetijger wrote:That must have been a serious impact, how can you not notice this?
Maybe during transport something fell over on the tank?

Yeah, that's what I asked myself too.... Been trying to figure it out, obviously something fell at some time. Not in the garage, so much I know. Not much to wonder about, bought a Dent Puller so we'll see if I can get most of it out.

skelly wrote:Interesting stuff,

I'm following this post as I am also building a racebike.

Cheers.
Skelly.

Nice, how far along are you. Any plans on what class to race?

Basically I just need a sealed belly pan and some engine covers to go. But of course I also want some more punch that my stock engine have before signing up.

Not collected the bike yet, so not very far apart from scoping out engine mods.
I'll start a thread once I get it home.

Skelly

Fixing dents

Finally got around to source a PDR tool (Paintless dent removal) for the dent in the tank. Seen a lot of clips on Youtube with people fixing any dent with just one pull. Well, it's not really that easy... No surprise.

Does work though, the technique is to glue the puller close to the edges of the dent and pull those, not the middle. Uses regular hot glue with a standard gun to fasten the puller tab, and it comes off real easy. Any residue is easily cleaned with alcohol.

Got one more pull to do, but need to strip the vinyl so done for the day, turned out decent. Not like new, still some very small irregularities making it slightly wavy but I'm good with that on a track bike.

So, I'm giving up on this....


No, not the bike just yet. Just the aprilia swing arm part. Too much machining I can't fix myself, so I'm thinking returning to stock will be the easier route. More option with people having done that before. The RSV swinger is about 10 mm wider where it sits in the frame so some machining and possibly repositioning of bearings will be needed. The aprilia also have their rear damper off to one side due to exhaust pipe from rear cylinder. So new fitting for the linkage have to be made up.

Don't feel like paying someone to have this done, so the swing arm goes to a Tuono with a dented swing arm instead.

I'll try getting a axle sleeve done for the stock axle to fit with the R6 wheel and see if I can find the lightest/easiest solution for rear brake to match. Hanging Suzuki caliper?

Rebuilding rear end

Goal: Getting a 5-spoke R6 wheel to fit in TRX swing arm with a 520 drive while keeping as much of the hardware unmodified for easy replacement in case of a crash.

So, going into the plans for remounting the stock swingarm I thought about getting a sleeve done like Cobba have done. But then I found this via another thread here: http://www.cco-classicracing.de/trx-850 ... lgenumbau/

Basically, just adapters either side replacing stock spacers and taking up the difference in diameter between stock axle and bearings in the R6 wheel. The one's in the link are for another wheel, and possibly not centered but the principle works. I just need to measure mine out from a centered wheel with aligned chain.

Also found on this forum that Cobba mentioned using a GSXR 2002 rear brake caliper so gonna try that if not too expensive to find: http://www.trx850.com/phpBB_forum/viewt ... 37#p116077

Will start by putting the swing arm back and hang the wheel in for some measurements. Need to find a brake too. Make drawings of the adapters and see if I can have them made by someone. Gonna have to get a new set of 172 mm dogbones somewhere along the way also...

Please do make drawings.
I wish that all the home engineers over the years had made drawings as we seem to be reinventing the wheel.