KTM RC8R TPS and dyno run!

[xrocket21]

Trying to prep the bike to put it on a dyno, turns out there's a bike dyno near me and will do 3 runs for $40 and I'm curious what it will make. Its +2 in the rear I think, pipe and a tune.

One thing I didn't think of at first is oil change, probably won't hurt to have fresh oil in it. The oil is up due to time not mileage so I only changed the oil and not the filter. I didn't ride more than 100 miles last year due to the collarbone.

Trying to teach them so they can take care of their own rides someday



Next issue is the TPS, It is a semi common problem on these.

At WOT I only get 96.5% throttle



The TUNEECU program I have does a diagnostic mode where it releases the servo to go to absolute 0 throttle, and you should have 0.56-0.64V, I am smack in the middle at about 0.6V



I adjusted throttle cable play and while it made the throttle feel MUCH better, it didn't help my WOT issue.

So the common fix of physically adjusting the TPS isn't a go for me, since my V is fine.

Next plan is to physically grind down the stop according to this:

https://www.ktmforum.co.uk/threads/tps-now-100.163333/

Once I can get this bitch to read 100%, I'm headed to the dyno to get my heart broken.

Gotta pull the seat, tank, airbox, and throttle bodies to get to it.

[FriskyDingo]

i'm sure your 105% on top of this with all the KTM site info, don't mean to insult you with a stoopid simple recommendation that probably won't work, particularly if you have already verified it is the "stop" keeping it from 100%...

but since you didn't mention if you tried the KTM throttle recalibration step, disconnect battery (15 minutes, overnight), reconnect, turn key to ON but don't start, wait for the full ECU/screen "warm up" then slow & steady turn throttle from full close to full open then slowly back to full close. Turn off, wait a minute, restart and check the TuneECU % again....

If it's the physical stop, obviously no help, but if it's just the throttle ECU calibration maybe 10% chance might help...

Good luck just hope you heal up & get to put some miles on that thing this summer

[xrocket21]

i'm sure your 105% on top of this with all the KTM site info, don't mean to insult you with a stoopid simple recommendation that probably won't work, particularly if you have already verified it is the "stop" keeping it from 100%...

but since you didn't mention if you tried the KTM throttle recalibration step, disconnect battery (15 minutes, overnight), reconnect, turn key to ON but don't start, wait for the full ECU/screen "warm up" then slow & steady turn throttle from full close to full open then slowly back to full close. Turn off, wait a minute, restart and check the TuneECU % again....

If it's the physical stop, obviously no help, but if it's just the throttle ECU calibration maybe 10% chance might help...

Good luck just hope you heal up & get to put some miles on that thing this summer

Thanks! Definitely NOT 105% on top of it lol. The RC8 R community is pretty weak. My friend got a 16 Repsol Honda 1000R SP and I'm a little jealous because there just such a MASSIVE increase in parts availability and knowledge.

Anyway, I was going by this thread originally, which linked to the other thread on the stop:

https://www.ktmforums.com/threads/tp...9#post-1078869

the last post was in May 2021 lol, I posted back in April and got no response.

I had seen rumblings of a throttle reset procedure, but I couldn't find anything online and it didn't say anything in my shop manual.

If this works that would be SO awesome! I will try it at lunch today, actually, Ill go unhook the battery now so it will be ready.

My fingers are crossed! I could get that dyno scheduled asap if this works!!!

[Kurlon]

Have you looked at the actual butterfly? If it's straight up and down with the throttle against the stop, grinding the stop is going to have you rolling past WFO and start re-closing the throttle in pursuit of a '100%' reading on the tool. If your closed throttle reading is dead in the middle of the range, I'd be inclined to bump the tps adjustment so it was on the high side of the range, but still in the acceptable range and see if that got it to 100% with a fully open throttle before grinding stops?

[xrocket21]

i'm sure your 105% on top of this with all the KTM site info, don't mean to insult you with a stoopid simple recommendation that probably won't work, particularly if you have already verified it is the "stop" keeping it from 100%...

but since you didn't mention if you tried the KTM throttle recalibration step, disconnect battery (15 minutes, overnight), reconnect, turn key to ON but don't start, wait for the full ECU/screen "warm up" then slow & steady turn throttle from full close to full open then slowly back to full close. Turn off, wait a minute, restart and check the TuneECU % again....

If it's the physical stop, obviously no help, but if it's just the throttle ECU calibration maybe 10% chance might help...

Good luck just hope you heal up & get to put some miles on that thing this summer

well, I did the KTM throttle calibration...



went from 96.5% throttle to 95.7% throttle

And, now it makes a solenoid like noise when I put it in TPS mode with TUNEECU that it didn't do before.

Oh well, was worth a shot!

- - - Updated - - -

Have you looked at the actual butterfly? If it's straight up and down with the throttle against the stop, grinding the stop is going to have you rolling past WFO and start re-closing the throttle in pursuit of a '100%' reading on the tool. If your closed throttle reading is dead in the middle of the range, I'd be inclined to bump the tps adjustment so it was on the high side of the range, but still in the acceptable range and see if that got it to 100% with a fully open throttle before grinding stops?

Ill take a look at everything once I get the tank and airbox off

[FriskyDingo]

well, I did the KTM throttle calibration...



went from 96.5% throttle to 95.7% throttle

And, now it makes a solenoid like noise when I put it in TPS mode with TUNEECU that it didn't do before.

Oh well, was worth a shot!

- - - Updated - - -



Ill take a look at everything once I get the tank and airbox off

DAM, that kinda sucks.... Perhaps I SHOULDN'T be doing that to my 690 at the start of each season...

Good luck trouble shooting, hope you don't need to disassemble too much..

[xrocket21]

DAM, that kinda sucks.... Perhaps I SHOULDN'T be doing that to my 690 at the start of each season...

Good luck trouble shooting, hope you don't need to disassemble too much..

IDK, it is a legit procedure

I just found it odd that it makes a noise now but didnt before. Maybe I adjusted the cables wrong and is creating tension when it closes 100%?

I wasn't complaining, I was just updating, I appreciate the help!

[Paul_E_D]

It's possible that it is simply designed that way. I know a lot of liter bikes will not actually give you 100% throttle opening.

[OreoGaborio]

WOAAAAAAAH woah woah woah woah............... are you telling me that all this time, we REALLY CAN'T actually USE all that POWER?!?!?!

[backinthesaddle]

It's possible that it is simply designed that way. I know a lot of liter bikes will not actually give you 100% throttle opening.

It's kind of interesting when you see some of the ads for ECU flashes for liter bikes:
ZX10R Throttle Derestricted (per gear)
Gixxah 1000 Derestricted electronic throttle valve (ETV) settings to allow 100% throttle operation

[butcher bergs]

100% throttle mechanically doesn't automatically equal 100% throttle electronically.

I'd be real careful grinding away at hard stops

[xrocket21]

100% throttle mechanically doesn't automatically equal 100% throttle electronically.

I'd be real careful grinding away at hard stops

Idk, I read something on the Internet once

[Zolden]

Whatever it is worth, I was never able to see 100% in tuneecu on my 990 SMR either and I followed the procedures to reset it thoroughly and multiple times when I was chasing an issue with it dying after 5k rpm (it was, as it always is, the regulator rectifier but tricky to detect). I think it maxed out at 98%.

[xrocket21]

Left the TPS alone, got it dynoed!!!

https://www.youtube.com/shorts/o4oToYC8iiQ





Jester Exhaust, Tune ECU B0334 tune, air fuel looks great! Dyno operator was very happy with it.

[Mgiossi]

God I love that bike......... Just had to say it

[xrocket21]

God I love that bike......... Just had to say it

It sounded SO FUCKING GOOD on the Dyno!

408 lbs dry with the stock heavy exhaust!

[Paul_E_D]

That is a super nice power/torque scenario for track riding.

[xrocket21]

That is a super nice power/torque scenario for track riding.

I have daydreams of being in good enough shape for a Jday season next year and taking this to a track day as well. I'd have to fit in those one piece leathers again...

The bike is such a beast for sure. I hate to speak poorly of the RC51, but the RC8R is so easy to move around, you almost just have to think about it and it does it.