How Important is the 150mV TPS Setting?

[Kiwi Dave]

My stock V11 Le Mans was running so sweet before I started meddling with it! First of all, I added the Stucchi crossover and Mistral silencers plus a Power Commander; downloaded the appropriate map and noticed a benefit.

 

Then I installed a FBF airbox eliminator kit. Again I downloaded a map close to my setup (I couldn't find one that matched exactly), and noticed further gains. So far, so good.

 

I then booked in for a dyno test to fine tune the system, so before the test I decided to check the TPS setting as I'm sure it would have an effect on the dyno results. The setting was very high (475mV verses 150mV) so I backed it down to the 150mV recommended setting. I even temporarily removed the fast-idle (choke) setup to ensure that it was not influencing things.

 

The dyno test has been postponed, and now in the interim my bike runs like a bucket of bolts! It spits back, hesitates, and explodes occasionally out the exhaust. I richened the "low" setting on the Power Commander with only limited results.

 

Question is, should I return the TPS setting to 475mV before the dyno test, or perservere in the hope that dyno run will sort everything out?

 

Thanks for any advice you can offer.

[callison]

150 mv is the setting the for 16M computers on the 96-98 Sport 1100i's. It doesn't work very well on them and obvicously works a whole worse on the 15M computer. The V11 Sport is more like 525 mv at it's preferred setting. Since I'm not absolutely certain what the optimum voltage is for the V11 Sport, I will defer to those that know better, but for now, return yours to the 475 mv setting before you damage your engine.

[Cliff]

Not sure if there is a difference as my 97 Sport Corsa (16M) , my 95 Cali (P8) and a late model ( 15M equipped EV ) all seem to have very similar settings.

 

I think the main confusion arises because there are two ways the TPS values are quoted.

 

One way is the T PS value at idle. This is the lazy way as it does not involve doing anything on the bike at all other than measure the value. The TPS usually gives about 1/2V ( 500mv ).

 

The factory calibration involves removing throttle linkages and backing out idle stop screws or what ever such that the butterfly valve is completely closed off in the throttle body. This is the factory calibration and comes out around 150mv.

 

I agree with Carl, put it back where it was.

[RacerX]

Another technical question that should be over on the GuzziTech page too...

 

Anywho, there seems to be alot of confusion on this. 150mV is the idle voltage, in which you have to disconnect the linkage to set, then re-connect and reset the voltage for "running" (in which the motor is *not* when you set it). This target OEM is 350mV... which is WAY lean. For most bikes the range falls in the 475~525 range... so, Dave, you were probably near ideal before you twiddled. You should stil be in town for this weekend's "Tech Day" just North of L.A.

Power Commander built maps are usually mapped around those voltages as well. Be sure to set it to the voltage usually noted in the Map's 'Notes' section.

 

ToddGuzziTech.com

Certified PCIII Tech

[Kiwi Dave]

Anywho, there seems to be alot of confusion on this. 150mV is the idle voltage, in which you have to disconnect the linkage to set, then re-connect and reset the voltage for "running" (in which the motor is *not* when you set it). This target OEM is 350mV... which is WAY lean. For most bikes the range falls in the 475~525 range... so, Dave, you were probably near ideal before you twiddled. You should stil be in town for this weekend's "Tech Day" just North of L.A.

  Power Commander built maps are usually mapped around those voltages as well. Be sure to set it to the voltage usually noted in the Map's 'Notes' section.

 

My 150mV was set with all linkages removed. This morning I returned this setting to 475mV, which produced a voltage of 540mV with idle just over 1000 rpm. I used the SM-V11S map file from the Guzzitech site. Things are back to normal, and I guess any fine tuning will occur when I can get on the dyno.

 

Won't be able to make your "Tech Day" Todd, as I've returned to Kiwiland. Summer is now in the southern hemisphere.

[Cliff]

My 150mV was set with all linkages removed. 

 

And both the idle stops backed out all the way ??

 

I leave the RH idle stop out the way all the time and just use the LH side. I also don't use the fast idle. It and the RH side cause some distortion of the throttle setup. Normal riding only supports it from the LH side

[Kiwi Dave]

And both the idle stops backed out all the way ??

 

Actually no, I've removed entirely the RH one, and with the linkages removed the LH one shouldn't have any effect. I also removed the circlip and fast idle mechanism (choke) from the RH throttle body to be totally sure.

 

One thing I haven't played with is the "throttle bypass screws" as I don't seem to be able to find them. I'm assuming they affect the idle mixture, and I would like to richen these slightly. Any directions?

[Cliff]

Actually no, I've removed entirely the RH one, and with the linkages removed the LH one shouldn't have any effect.

Thats correct.

 

If memory serves the air bleed on my sport are under the throttle body going vertically up.

[JuhaV]

Hi,

 

To be sure that the butterfly is fully closed for the 150 mV adjustment, I always remove the plastic air inlet tube from the injector body and take a look inside. I also run with the air screws in fully closed position.

 

br, JuhaV

[Guest Bruce]

Likewise the air bleed screws on my sport are on the bottom. An inspection mirror makes it an easy adjustment.

 

My '00 Sport is essentially stock and I advanced the TPS to .65V with the bike off and everything hooked up. Mostly I was hoping to richen it up a bit as it felt lean running and had a very pronounced ping under some conditions ( ie it felt lean and when opening the throttle it seemed to get real lean ).

 

The ping is gone, the plugs are darker, and it seems to have filled in the 'hole' between 3500 and 4k for the most part. I used to try and ride around the 'hole'. Now its not an issue ( actually my tach died recently and it doesn't matter ). This of course is a cheesy trick and not a subsitution for a better map!

 

IMHO the TPS is how your right hand communicates with the computer; ie speeding up, slowing down, or steady state. So a lower than spec setting tells the computer you are trying to slow down and therefore would appreciate it if the computer were to deliver less fuel to the engine.

 

With all of your mods I'd use the stock setting as it would seem that various maps indirectly use this as a reference point.

 

Always an interesting topic, let us know how you make out.

 

Best of Luck

 

Bruce