thundercat rider Posted July 5, 2009 Report Share Posted July 5, 2009 Today I found out my TPS on my thundercat is faulty (thank you Haynes!). It caused little hiccups on steady throttle, and created some buzziness. It also hastened the demise of my clutch plates and basket/hub. It has been faulty for 1000kms at most, and started giving clutch rattles. Furthermore, I have a feeling it was never properly adjusted in the factory (gut feeling), causing poor idle I think (hiccups came later). Can anyone tell me what damage it may have caused to my bottom end? I also would like to say to people it might by worthwile to check your ignition system (including TPS) with a workshop manual and a multimeter before fiddling with carbs or powercommanders /ecu's. That way you don't have to throw money on a dyno. Link to comment Share on other sites More sharing options...
wavydavy Posted July 5, 2009 Report Share Posted July 5, 2009 Are you *sure* it's the TPS? Only you've not mentioned the rev counter repeatedly pointing to 3000rpm(IIRC) when you are riding, which it should if the TPS has gone awry.... Even if it is the TPS, I can't see how that alone will make any difference to the clutch or the bottom end (assuming you mean mechanical bottom end - big ends etc - rather than the 'bottom end power') Carbs out of balance and other fuelling might cause the problems you state, but the ChunderFlap tells you if TPS or the fuel tank sensor are faulty (3000 pointer or 8000 pointer respectively) Dave Link to comment Share on other sites More sharing options...
MonkeyJim Posted July 6, 2009 Report Share Posted July 6, 2009 Are you *sure* it's the TPS? Only you've not mentioned the rev counter repeatedly pointing to 3000rpm(IIRC) when you are riding, which it should if the TPS has gone awry.... Even if it is the TPS, I can't see how that alone will make any difference to the clutch or the bottom end (assuming you mean mechanical bottom end - big ends etc - rather than the 'bottom end power') Carbs out of balance and other fuelling might cause the problems you state, but the ChunderFlap tells you if TPS or the fuel tank sensor are faulty (3000 pointer or 8000 pointer respectively) Dave I *agree* with Dave. Doesn't sound like TPS to me. Are you sure you've read your Haynes properly? even if the TPS was way out, it wouldn't have any effect on the clutch. Totally unrelated, as is 'the bottom end'. most likely your carbs are out of balance - get them done properly and set the idle speed to what it says in the manual. then have a look at the TPS Link to comment Share on other sites More sharing options...
TheFlymo Posted July 6, 2009 Report Share Posted July 6, 2009 I thought that TPS on carbed bikes was generally for emission/noise control only, and IIRC on Suzukis, to limit the power in the first few gears. When I had a Bandit 1200 the general wisdom was to junk it as it didn't do anything. Link to comment Share on other sites More sharing options...
thundercat rider Posted July 6, 2009 Author Report Share Posted July 6, 2009 It's not broken in the sense it is not functioning anymore (it would have given error codes on the tach), but it was sending the wrong signal to the tci, fooling it in thinking the throttle plates were more open then they were in reality. This was advancing the ignition I believe. Anyway I adjusted the sensor, it still has too much resistance by 50% percent on closed throttle (ohms), but the hiccups are gone when riding after the adjustment. The plastic shell of the sensor is broken, and when pushing gently on it/cables, it sents a signal to the tci (it shouldn't). I wouldn't be suprised if it was affected by normal engine vibes and air flow/wind. Link to comment Share on other sites More sharing options...
Gixxerthou Posted July 9, 2009 Report Share Posted July 9, 2009 I thought that TPS on carbed bikes was generally for emission/noise control only, and IIRC on Suzukis, to limit the power in the first few gears. When I had a Bandit 1200 the general wisdom was to junk it as it didn't do anything. Hi, General Section Mong here.... The TPS on my EFI bikes tells the ECU what position the throttle body butterflys are at and how much fuel to pump in, after calculating cam position, ambient air temperature, crank position etc etc... junking it would cause my bike to NOT WORK. Bandits are carbed... so shouldn't need one anyway. There is a resistor that retards the ignition that impedes the voltage sent to the ECU for the first 3 gears on Suzuki models, this can be bypassed by fitting a 20p resistor (think its a 15k ohm one) if you do it yourself, or by giving some twunt £30 online for a Retard Eliminator. HTH Link to comment Share on other sites More sharing options...
MonkeyJim Posted July 9, 2009 Report Share Posted July 9, 2009 Hi, General Section Mong here.... The TPS on my EFI bikes tells the ECU what position the throttle body butterflys are at and how much fuel to pump in, after calculating cam position, ambient air temperature, crank position etc etc... junking it would cause my bike to NOT WORK. Bandits are carbed... so shouldn't need one anyway. There is a resistor that retards the ignition that impedes the voltage sent to the ECU for the first 3 gears on Suzuki models, this can be bypassed by fitting a 20p resistor (think its a 15k ohm one) if you do it yourself, or by giving some twunt £30 online for a Retard Eliminator. HTH indeed Rog I think that's what the TPS generally does. but my R1 has carbs [carbs?! how very dare you] AND it has a TPS. So nerrrrrr! quite a few Yam's of the same vintage had carbs and a TPS. I think - on the R1 anyway - the TPS has something to do with the engine management, or something. I seem to recall that the faster you open the throttle, the harder the spark plugs spark, or some such bollocks. Now, piss off back to general section where you belong, ya mong! Link to comment Share on other sites More sharing options...
fran9r Posted July 9, 2009 Report Share Posted July 9, 2009 Bandits are carbed... so shouldn't need one anyway. or by giving some twunt £30 online for a Retard Eliminator. HTH Wow...£30 to rid my life of all the retards is a bargin. Where can I buy such a thing? TPS is used on a lot of late model carbed bikes... Edit -beaten to it...but yes it's timing related. Link to comment Share on other sites More sharing options...
TheFlymo Posted July 9, 2009 Report Share Posted July 9, 2009 Hi, General Section Mong here.... The TPS on my EFI bikes tells the ECU what position the throttle body butterflys are at and how much fuel to pump in, after calculating cam position, ambient air temperature, crank position etc etc... junking it would cause my bike to NOT WORK. Of course, which is why I said "on carbed bikes"! On the Bandit it was for emission control only. EDIT: For the retard eliminator, it's worth going the resistor/transistor route, otherwise it buggers up your idle in neutral. For the hassle of getting connectors, soldering it all up and packaging it nicely, I just stumped up for the Ebay item! Link to comment Share on other sites More sharing options...
Gixxerthou Posted July 10, 2009 Report Share Posted July 10, 2009 Of course, which is why I said "on carbed bikes"! On the Bandit it was for emission control only. EDIT: For the retard eliminator, it's worth going the resistor/transistor route, otherwise it buggers up your idle in neutral. For the hassle of getting connectors, soldering it all up and packaging it nicely, I just stumped up for the Ebay item! Hi, general section mong back again... Spot on. The main problem with the TRE is that it makes the bike think it's in 5th and 6th gear all the time, which can cause problems starting the bike and when it's in nuetral, causing tickover problems. Link to comment Share on other sites More sharing options...
Kayla Posted July 11, 2009 Report Share Posted July 11, 2009 TPS works on carbed bikes to allow the use of a 3D ignition map (the cdi looks up the throttle position and rpm which then sets the advance), rather than a 2D one (rpm, advance). I don't know if it's for emissions or fuel economy. edit- just to add that disconnecting the TPS on the TRX sets the throttle position as 'fully open' and moves the rev limiter up a touch. Apparently it's worth a bhp or so, but I did it when I got the FCRs sorted so can't say either way. Link to comment Share on other sites More sharing options...
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