The TRX900 Project kicks off

[Mincehead]

I watched a 2.2 ltr S & S motored Tractorson chop be turned over on a tiny lithium cell the size of a packet of Marlboro. The starter button was held til the starter motor began to smoke, it had THAT MUCH capacity. The Shorai Cobba talked about are great, never heard a bad report about them yet.

[coxylaad]

it will get its chance. hopefully it wont set my bike on fire

[coxylaad]

Tip sensor, air pressure sensor and battery box installed.





fits snugly under the tail unit. I just have the starter solenoid, the power commander and the datalogger to make brackets for, and a whole host of wiring length alterations to do.

[dandywarhol]

Keep them coming, do you think these high level zorst pipes are big enough?

[coxylaad]

they are tuned for length

[coxylaad]

Croft 21/04/2017 fast group on the blade. it was fun, if a little serious!

https://www.youtube.com/watch?v=Yn2z2hS2mfk

https://www.youtube.com/watch?v=JHpUsRVwqAg


There was a lot of chasing shadows, and there were some proper racers out there making everyone look stupid. All good fun though.

[coxylaad]

my faster mate followed me on one of the sessions, its actually quite good viewing:
https://www.youtube.com/watch?v=Yy37oQkMdss


anyways back to my TRX - a few years ago when i first put the TRX together I was querying the shock height and dog bones as the swingarm seemed to sit quite low.

both were stock so I assumed it was ok and just some visual trick of the eye or something, although I should have realised something wasnt right as on the sidestand the bike was virtually upright. (I assumed it was something to do with the forks)

fast forward 5 or so years and I am looking at ressurecting the TRX for cadwell park in august, and I noticed that the pivot point of the thunderace although in the same longitude plane, hangs about 10mm lower than the trx one. which will effectively push the swing arm up 20 or so mm at the wheel and make the bike sit lower.

I am going to fit some shorter dog bones to bring it back to the stock height but I might actually take the swingarm out over the winter and have it welded to the correct height.

[coxylaad]

TRX is going back into track action in august for a 2 day event at cadwell.

With that in mind I am adding some of the trick bits I have collected over the years from buying and selling bikes, starting with a brembo 18-20 radial master cylinder and a domino quick action throttle.





I am going to have to modify the front fairing support as the new lever hits it on full lock.

[dandywarhol]

See if you can get some sponsorship from a well known pizza chain

[cobbadiggabuddyblooo]

OUJWOP Pizza ????

[coxylaad]

love a dominos pizza!

I am not sure why the throttle its called domino, maybes it means something different in Italian

the throttle is now just less than a quarter of a turn which is how I like it.

[coxylaad]

ok a bit of an update on this one.

The trx is hitting the track again on 29th and 30th of August, seems like a long way away but i know it will be gone in a crack and I have a half completed bike.

I have been looking at swing arm angles on the bike and realised that the thunderace swing needs shorter dogbones due to the lower position of the dogbone mount.

I have experimented at cost :-[:



and came to the conclusion that to get the stock angle I need 20mm shorter dog bones, I settled on 162mm ones (stock trx is 182mm) it now sits nice and I get the benefit of extra ground clearance in the corners. I thought the swingarm didnt look right in the pictures of it on track, but I couldnt be sure:


Looking at it it seems pretty obvious now. I should have investigated further but the bike seemed to go well enough. I have had one rear end slide on the bike, and thinking about it, I ride a lot harder now so it was probably a geometry thing. The angle was sutch that instead of having anti squat on the throttle i was getting extra squat as the rear wheel axle was pulling over the top of the swing arm axle.

So here we are with 162mm dogbones. fyi the thunderace stock dogbones are 164mm...should have rung some bells.


Moving on I have built this new rear subframe with road work and load bearing in mind - nice and sturdy and a lot lower than the previous track version to take some weight off the wrists when I am bimbling through villages at 28mph. Now its going back on track I am having to modify the bugger back to somewhere where I like it for track use (ar5e [filtered] up shoulders over the front end)

Here is the profile view that will work for me:




Sorry about the image sizes, not sure how to sort that

[dandywarhol]

Look at that lovely TDM900!!!!

[coxylaad]

hes looking good isn't he

[coxylaad]

Finally got the old girl back on the road for a shake down ride.

A couple of thoughts immediately sprung to mind

'My god this is loud' like offensively loud! How this ever passed a noise test is beyond me. It needs an airbox of sorts and a proper exhaust. what I have on it looks cool but its not enough. I cant be doing with pleading with the noise testers to let me on on every track day I do. That said the noise tests dont suit the trx. yes it will breach the 105db static test but because it only revs to 8500rpm it never bothers the fly by tests at all, which are the most important ones. some of the supersports 600s piss the static test and they sound like they are ripping space time continuum apart down the straights. But the static test comes first so its a moot point if they dont let you on the track in the first place.

Next thought was ' This isnt as quick as my TDM' it feels like it has a bit more low down grunt than the tdm, but as soon as you hit 5000rpm the tdm is pulling notably stronger. I am going to try this updated ecu I have loan of, but I suspect the engine mods are making the difference.

Finally now that I am getting used to a proper road bike again, I find myself wondering how I managed to tour Scotland on the this!

So initial thoughts are, If the trx turns out to be the track bike I want it to be (to replace the fireblade) then I will build myself an engine with the following spec:

TDM 900 engine with:
high lift cams
Gas flowed big valve head matched to BMW F800 43mm throttle bodies
raised compression
940cc JE Pistons
carillo rods
free flowing exhaust.

Hopefully with that lot it should make 110bhp + fingers crossed. The thoughts are super sport 600's are still only knocking out 110 to 120bhp, so if I can match that type of max power output and have the extra punch out the corners it should be weapon for even the fast group.

failing that I have been looking into a plan B. its a bit drastic but I am considering buying and breaking an XT1200z Super Tenere' I have done some basic calculations I think I could claw a large portion of the money spent back and still be left with the 1200 engine, and electronics. This would give me a fly by wire throttle with power modes and options for engine braking, traction control ABS etc. and the bike has 110bhp stock. If I ditch the massive Euro4 cat converter and fit a free flowing exhaust I could be straight up to 120bhp
Obsticles I can see for this are:

1) I am not bothered about the ABS but I would need the sensors for the traction control, no big deal however I would need to find out how it calibrates it wheel sizes, as the S10 has a 18 or 19 inch front wheel and it will rotate slower than the rear for the same speed. I am hoping it auto calibrates itself.

2) its shaft drive. I considered just using the S10 frame and retaining the shaft drive as when you look at it its not too dissimilar to the trx trellis frame. but the wheelbase is a little long and the steering head angle is a bit relaxed. fitting the shorter r1 forks will steepen the steering head and reduce the wheelbase but not by that much I would have thought. Plus I am not sure I want a shaft drive track bike.
I would have to see if I can convert it to a chain
The S10 Frame:


I would be running the the fine line of 'actually this isnt a TRX any more!'

Its all just speculation at the moment but I am giving it some serious consideration.

Lastly I would be ripping apart my current TRX which seems like a massive shame, as I have put a lot of graft into it and its a very unique bike in every way.