won't run smooth at constant revs

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shark
Cucciolo - the Lil Pup
Posts: 4
Joined: Mon May 26, 2014 12:59 am

won't run smooth at constant revs

Post by shark » Mon Aug 18, 2014 6:30 pm

Hi all, am having a bit of trouble trying to source the problem on my 860gt of not running smoothly when the throttle is kept in the one place. It has no trouble starting, idling or when under throttle. It actually runs really nice seeing as I have tuned it and rebuilt the carbys. ( Surprised me ) but if I hold the throttle in the one position to keep at a constant speed she farts and splurges a bit. Not really bad but very annoying. Any one else out there come across this problem? It still might be a problem with the carbys, as I said, I did re-kit them. Thanks, I love this site.
Mark.

Ray O'Donohue
Parallel Twin
Posts: 119
Joined: Tue Oct 13, 2009 8:11 am

Re: won't run smooth at constant revs

Post by Ray O'Donohue » Tue Aug 19, 2014 4:54 am

One possibility among many: worn out carb bodies/slides.I don't know if Dellorto carbs are prone to this,but we used to fix Brit bikes that did this with new slides or (dirt cheap in those days) entire new carbs. Obviously you also want to look at the ignition and everything else.Vaccuum leak at the manifolds?etc etc

shark
Cucciolo - the Lil Pup
Posts: 4
Joined: Mon May 26, 2014 12:59 am

Re: won't run smooth at constant revs

Post by shark » Wed Aug 27, 2014 5:53 pm

Thanks for the advice Ray, I will check the slides in the carb body's this morning. I have had new rubbers put in at carbie mounts and sprayed with crc when running to check for vacuum leaks. What would I be looking for in the ignition if it runs well through every stage except constant speed? When I first bought the bike it had a bad problem of one carbie not running right and it took me a while to find the choke cable splitter had been cable tied on to the frame and one of the cable's to the carbie had been cable tied out of its seat by 5mm. I have removed the choke cables altogether now but still have this farting coughing problem a little. I'm not very confidant with this electronic ignition, I might go through the manuals again and see if I can find anything. Thanks again Ray.

saraceno59
Cucciolo - the Lil Pup
Posts: 21
Joined: Fri Feb 15, 2013 1:46 am

Re: won't run smooth at constant revs

Post by saraceno59 » Fri Aug 29, 2014 4:28 am

Hi, i have exactly the same problem with my 750GT. With a little bit of tunning at the carbs it got slightly better, but its still there. I am thinking of moving the needles one position down, to see what will i get.
1973 GT750, 2000 SS750, 1996 Yamaha tenere 660, 1980 Yamaha LB50

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