Triumphrat

reay21

Hi,
I have just purchased my first Triumph (2 weeks ago) and have noticed an issue that I wanted to ask for assistance on. Please let me know if anyone has any ideas on the issue/s and/or resolution.
Well, I purchased a 2000 Triumph Sprint ST 955 (which I absolutely love) and have found that the RPMs are surging.

This is basically what I have found....
When idling, the bike will be at ~1500 rpm and bounce between 1200 - 1800 rpm. I don't think that this would normally be an issue to worry about if this was only happening when idling. But it does the same thing at any rpm. (Example - If I roll the throttle to say... 5000 rpm, the rpm will surge +/- 300 rpm)
I have found this to be extremely annoying because the bike has quite a large engine and I can easily feel the surging when riding.

Mileage - 18,500 miles
Valves adjusted @ 12K (per previous owner)

Thanks in advance!
Brent

KitNYC

There's a scheduled maintenance chart for your bike here:

http://www.triumphrat.net/downloads/...ST_to_2001.pdf

Throttle bodies should've been sunc at the 12k service, but maybe they weren't? Could also be an air leak.

You may wish to ask in the Sprint Forum if you haven't already.

Congrats on your new ride!

Cheers,
-Kit

Jhumphrey

Look around the idle air control valve for a misfit or cracked tubing, check the throttle cable to see if throttle bodies return to closed, it would be nice also to review the TPS output to see if thats actually fluxuating as well.