Yamaha TRX850 Enthusiasts Forum

Purchased Some second hand fcr's from a trx with no TPS mount.Being technically challenged should i just try them without or see if it is possible to purchase a TPS mount[have searched some forums like KTM/Ducati were people fabricate them,looks difficult]
I have over racing pipe and one of Brian's ECU's.
Suggestions appreciated

craybait wrote:Purchased Some second hand fcr's from a trx with no TPS mount.Being technically challenged should i just try them without or see if it is possible to purchase a TPS mount[have searched some forums like KTM/Ducati were people fabricate them,looks difficult]
I have over racing pipe and one of Brian's ECU's.
Suggestions appreciated

I ran with TPS mod for some years, tad sluggish off the line but no biggie. With ignitech´s TCIP you can dial it out.
If you REALLY want one i bought my FCR´s from keihin in Germany who make their own TPS mounts...

I would try and track one down as having an active tps does make a positive difference and unlock that much more from a fabulous carburettor. An optimised fcr is amazing to use and enjoy.

thanks for the help,
had a look at the fcr's today,they have a rod protruding from the left hand side which has a flet end for tps ,but no mounting flange.
will ring a keihin dealer to see what they have or try and fabricate ! later

Killerwhale wrote: I ran with TPS mod for some years, tad sluggish off the line but no biggie. With ignitech´s TCIP you can dial it out.
If you REALLY want one i bought my FCR´s from keihin in Germany who make their own TPS mounts...

That's funny you say that. I just connected my Ignitech unit to the computer for the first time.
I see the TPS is disabled by default but you do get readings from the TPS.
What I don't understand is that closed throttle gives a high voltage (like 4,0V) and fully open is about 0,9V. In the ignitech program it looks like the opposite is expected; because with throttle closed it reads higher voltages at "100%" and fully open it lowers to 0%.
Shouldn't this be the other way around?
I hope some of you can clearify on this.

Yep, 100% should read approximately 4 volts + or - a few points.
0% Should read the lower value usually under 1 volt.

I've sent Jiri at IGNITECH a message about this issue so as soon as i get a reply I'll let you know Robert.
It may just be the referential voltage pin ( 17 ) and the ground may be reversed.
I recall something about 99 model TPS may not work but mine is a 99 model and works fine.????

Tarwetijger wrote:

Killerwhale wrote: I ran with TPS mod for some years, tad sluggish off the line but no biggie. With ignitech´s TCIP you can dial it out.
If you REALLY want one i bought my FCR´s from keihin in Germany who make their own TPS mounts...

That's funny you say that. I just connected my Ignitech unit to the computer for the first time.
I see the TPS is disabled by default but you do get readings from the TPS.
What I don't understand is that closed throttle gives a high voltage (like 4,0V) and fully open is about 0,9V. In the ignitech program it looks like the opposite is expected; because with throttle closed it reads higher voltages at "100%" and fully open it lowers to 0%.
Shouldn't this be the other way around?
I hope some of you can clearify on this.

Take TPS unit out and rotate it internally so closed trottle equals 0v?

Gidday Robert,
Quick confirmation from Jiri at IGNITECH and as I suspected , just reverse the wiring on +5 v with the ground to solve your problem..

I thought to ask here first before contacting Ignitech. But Jiri is fast with replies isn't he?
Great, I will look at the wiring, for swapping at the TPS or at the unit itself.
Now I come to think of it, it could be because the TPS is on the other side of my TDMR flatslides but I'm not sure.
Thanks lads!
Can I expect a big difference with/without TPS?
I have to admit the bike runs very well without it, with a lot of power and fuel consumption at least 22 km/l.

Bingo...
Will work back to front with the TPS bolted on the other side.
I'll make Rich aware as he has TDMR 40's too.

cobbadiggabuddyblooo wrote:Gidday Robert,
Quick confirmation from Jiri at IGNITECH and as I suspected , just reverse the wiring on +5 v with the ground to solve your problem..

I tried but I still don't get it, as it doesn't work.
8<
Edit: sorted.

Purchased the TPS mount Killerwhale suggested and it fits perfectly onthe second hand FCR's I got from south australia. Have not fitted the carbs to the bike yet as I am moving to victoria end of feb and riding the bike around Tasmania march the 6th and it is going well now i replaced a dud iridium Plug . So will fit them end of March ,any suggestions on a mechanic/dyno in Victoria. I was think of Carl Batey [cafe carl] at wattle flats Bathurst.

Hi Scott,
Check your maps as Bathurst is in NSW which is a very large distance from Melbourne.

Thanks Alan,
In Wyndham at the moment must have fried the brain, Carl used to be in Bathurst and I assumed when he moved Wattyl Flats was not far.
Thanks for the tip,