adjusting throttle bodies and TPS

[Guest Warren Rhen]

Okay I did the throttle bodies today and I must say it is now running better than it has since I brought it with 1475 miles on it. The problem is I used the instructions from this website www.obairlairlann/~reaper/bmw-bike/guzzi/balance.html and when It was talking about checking the TPS the picture and any other info was missing. Which wire on the TPS do I put my positive lead from my voltmeter to to see if I have 500mvolt reading. IF I have a smooth idle and good balance and don't have a 500mvolt reading do I move the TPS until I get that reading. I also installed a lock nut on the big knob for adjusting the balance hopefully to keep my adjustments longer.

[Guest Brian Robson]

There are 3 wires from the TPS and the ones you need are the two outer ones. Pins inserted into these two wires and connected up to the voltmeter will either give a positive or a negative reading, in which case reverse the multimeter contacts and this is the reading you use when adjusting.

[dlaing]

500 mV is an estimate and assumes that your CO, valves and idle are set to something kind of specific that nobody has bothered posting (to my knowledge)

The 'factory method' is to measure voltage with the idle screws fully retracted, and to use the lower voltage of 150mV, according to the manual, which specifically (correctly???) says,

 

"27CARBURATION PROCEDURECheck of the starter control cut-outIn the event that the throttle valve potentiometer has beenreplaced, removed or deregulated, before carrying out anycarburation procedure it is necessary to adjust it onceagain, following the below instructions:•Detach the connection rod between the throttle bodies;•Using a tester, check that the potentiometer with theclosed throttle body indicates150 mV. If the values aredifferent,  loosen  the  two  fastening  screws  andreposition it correctly;•Adjust the throttle bodies using the adjustment screwuntil bringing the idling speed opening to 3,2°-3,6°;•Attach the connection rod between the two throttlebodies;•Check that the by-pass screws are completely closed;•Bring the RH side body’s adjustment screw flush;•Connect a vacuometer to the sockets on the intakemanifolds;•Adjust the cylinders’ equalization using the throttle bodyadjustment screw;•Check  that  the  equalization  is  maintained  inprogression;•Check that the engine’s idling speed is 1050 r.p.m.;•Bring the oil to a temperature of 80°C;•With the engine idling, check that the CO value isbetween 3% and 3,5%. If this is not the case, adjust itby varying the  Trim.EPROM value on the software’sActive Test page.•Check  the  r.p.m.  and  the  equalization  of  the  twocylinders once again."

 

Yah, it reads like a bad translation, and you probably don't have the $500 diagnostic software...which is why Ian's and other's instructions are so valuable.