78 GS1000- won't idle and runs rough below 2500RPM

[Guest]

Title says it. Last fall, just before I put the bike away for the winter I changed the oil and spark plugs then went for a ride. I noticed then at low speeds the engine was rough but after 2500rpm it smoothed out and ran great. So I put some stabil in it and put her away for the winter. Earlier this week I tried and tried to start her but got nothing but the sound of the starter. Battery was changed last summer and was sitting on a trickle chager all winter so I figured it was still too cold.
Today it was in the 50's so I tried it again and with a little help from some starter fluid it fired up. It was running really rough (much worse then ever) and backfired 5-6 times. I looked over the service manual double checked my plugs and saw the gap was too large so I regaped the plugs checked all the wires and started her up. This time no backfiring (YEA!!!) but still ran rough under 2500 RPM. Above 2500 RPM it sounds great but below it almost sounds like (dare i say it) knocking. The service manual is telling me to clean and adjust the carbs but since I'm broke and scared of messing with it myself I figured I'll ask. What else can I do? In the morning I'll be calling some shops. How much should this cost? Thanks for reading my frustrated babbling. Any help or advice would be much appreciated. Thanks.

[salty_monk]

Have the carbs been cleaned recently at all? If not then that is likely your problem. Replace the O rings too with a set from Cycle O rings.

Don't take it to a shop, learn to do it yourself, you'll get a better job too.....

Dan

[FreshmanJoe]

Never been done in the 3 yrs I've had the bike but I've always suspected it needed to be done cause a tank of gas only lasts about 75-125 miles. And that was last yr when the bike ran best. And the more I think of it and read up on it the more confident I feel about doing it myself. The only thing is I'm known for breaking stuff more then fixing it and I REALLY don't want to mess this bike up. So I was going over to bassclifs site to look some stuff over. How easy is it to screw up? Any tips for a newbie on how to get it done right? What do I need to have on hand?

[FreshmanJoe]

Do you suspect they need to be cleaned or synced?

[FreshmanJoe]

Just read this

http://www.instructables.com/id/How-to-Clean-Motorcycle-Carburetors/

and WOW it can't be that easy. Would something so simple really make it so my bike idles and runs properly?

[Nessism]

Here is the VM carb rebuild instructions...http://www.thegsresources.com/garage...rb_rebuild.pdf

Cycleorings.com for carb and intake pipe boot O-rings.

Be careful with the pilot fuel screws, the tips are sharp and like to break off in the carb bodies.

Short cuts are long cuts when it comes to rebuilding carbs. Do the job right one time, it will save lots of headaches in the long run.

[FreshmanJoe]

So the carbs are coming off next weekend and getting taken care of and while I was at it I was going to adjust my valve clearance and replace my petcock. Can anyone think of anything else that'll help peformace? Was kicking around a few hundred mile weekend camping trip latter in the summer and want it running top notch.

[Big T]

Joe

did you get a Megawelcome from BassCliff?

Everything you need to know is in there