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throttle position sensor

Posted: Mon Apr 14, 2008 6:42 pm
by johnl
well, i changed the clutch at the weekend, no probs but the bike still runs like a dog ( see thread 'any ideas ).

The bike will not go over 90 and often gets really bad dropping down to a top spead of 70 before going back to running bad and a top speed of 90.

It lurches all the time. If you try and use full throttle it just shudders and holds back.

so far i have done

- fuel filter
- air filter and cleaned out airbox
- changed the coil
- changed the ht leads
- new spark plugs
- disconnected lambda/oxygen sensor ( no differance )
- valve clearance and end float
- balanced throttle bodies
- removed and hosed out fuel tank a related tubing

So, does anyone have any experience of the throttle position sensor going wrong? Same for the fuel pressure regulator?

I do no think it can be the hall sensor as they seem to cause the bike to cut out when hot ( so I have read ).

All the cables would appear to be routed and working correctly as the throttle bodies balanced fine.

Posted: Mon Apr 14, 2008 7:09 pm
by r550s
'pologies if you've already done it - but maybe look down the throttles to make sure that they're opening evenly throughout their full travel as you twist the throttle. I'd re-check the throttle operation first, based on what you've described. Don't assume anything, these things have more throttle cables than, erm, something with a lot of throttle cables, ahem.

Re: throttle position sensor

Posted: Mon Apr 14, 2008 10:44 pm
by nab 301
johnl wrote:well, i changed the clutch at the weekend, no probs but the bike still runs like a dog ( see thread 'any ideas ).

So, does anyone have any experience of the throttle position sensor going wrong? Same for the fuel pressure regulator?

.


No experience of the tps but I suppose the only way to check the regulator would be to check the fuel pressure ,or maybe look at the plugs /do a plug chop /rolling road ? compression test ? Did someone suggest poor connections on the injectors?
You might be able to tell from the plugs if it's running rich lean, or can you substitute any parts from that spare bike of yours? :wink:
Nigel B

Posted: Tue Apr 15, 2008 5:26 pm
by oyster
This sounds like a fuelling problem. Wiring to the injectors. Fuel to the injectors. Injectors gummed. The above are tiresome checks. Removing the injectors is easy, swap them over it's a good way to check all connections. Crank the engine with the injectors off, fuel should pump out of the open hoses.

Posted: Wed Apr 16, 2008 5:59 am
by Paul
one thing you could try:

1) turn the igntion on, but don't start the bike
2) twist the throttle grip all the way from fully closed to fully open two or three times

I think you only need to do this if the battery has been disconnected, but no harm in trying it.

Hope this helps,

Paul

Posted: Wed Apr 16, 2008 7:02 am
by johnl
thanks for the replies.

I have swopped the TPS with my other 1100s but to no avail.

Alas I shall have to face my fears and book it in with the dealer to go on his magic computer.

I think now it can only be the hall sensor or chaffed wiring. Everything else has been changed.

I shall let you kow the results.