was riding the '91 GSPD today. The bike has 78,300 miles and a recent tune up ~2,000 miles ago. It has a Stayntune (sp?) muffler with 7 disks. The weather was clear and in the mid 80's. It was running great until I got to some stop lights. As I was waiting to proceed I noticed the idle was in the 2000 rpm area. I checked the trottle cables in the carbs and they seemed to be in place. The next grouping of lights, the idle started at 2000 and creeped up to 3000. I hightailed it home and started to look. No luck, everything seems in place. Any idea's where to look? What to do? Thanks in advance. Rob Lessen '73 XL250 '91 R100GSPD '95 R11RS '05 R12RT
One cause of increasing idle can be a bike that wasn't warmed up enough when the carbs were synced. Another can be airleaks in the rubbers etc. JT
Run a propane torch around the inside of the carb bodies with the engine warmed up and idling, and if the idle drops when it's near the starter enrichener covers, that's your problem - the gaskets have shrunk and the covers are leaking air. mully
Thanks blake!! I've just had a few minutes to poke around. Bette has me politiciting after work. Plus the 100 degree heat is back. I may be able to dig in later this week or the weekend. How's the family?? Rob
Rob, Same answer, different forum. :) Rob, Couple of ideas......... Clean and lube the 'bean can' advance mechanism. The grease can harden and when hot, the plate sticks in the advanced position. To test, disconnect the battery, remove the front cover. Reconnect the battery and take it for a ride. When it begins to fail, stop and see if you can rotate the advance plate and lowerthe idle RPM. Another source can be air leaks around the carb spigots or the rubber hoses. Spray some WD-40 at these areas when it is idling high to see if it drops. If so, fix the leaks. : )) StainTune mufflers do NOT have 'plates'. You must have an old Super Trap on there. :) Mick Tucson
when mine did the same thing I found that one of the lower choke cables had broken and the choke was stuck partway on. One the bike is running, push down on the choke actuator arms to make sure they are fully open.
THanks Mick, I'll start this weekend. The rubber bits in front of the carbs look new but I'll break out my supply of WD-40. Would air leaks cause the increased idle when warmed? As for the muffler, yeah, my bad, it's a Super Trap. Thanks again. I'll let y'll know what I discover. Rob Lessen Arma, KS
Boy I want that to be the problem. I really don't want to break out my wrench. It always gets dirty and I have to clean it. Thanks I'll look at it first. Rob Lessen Arma, KS
Rob, Yes, air leaks will cause an increased idle but from your description, I'd bet it's the advance unit. Mick
Another vote for choke cable(s).SOLO LOBO diagnosed the same fault for me a couple of months back. Had same symptoms, bike would start fine, run OK for a few miles, then the first time I came to a stop the tickover began rising to 1500rpm then 1750 rpm with no discernible cause. Choke cable on my bike ('91 R80GS) came in three pieces and took about ten minutes to fit.The only mildly difficult bit was the plastic divider where rhe cables split which had clearly never been touched since the bike left the factory. The same symptoms will show if the screws covering the vacuum plugs are missing from bottom of carbs (don't ask me how I know!). My cables went at 37,000 miles. From other people I have spoken to life of all control cables seems to be somewhere in the 35-45000 mile range.Given the mileage on your bike seems due for a second set of control cables soon.
Check out this thread on same subject.. http://www.advrider.com/forums/showthread.php?t=141196&referrerid=23478
And to be honest, I only know because I checked for air leaks, re-adjusted my valves sixteen times and pulled out a considerable amount of hair before I checked my cables.....
the heat is cutting into my riding time a bit as well. i haven't even thought about riding my dirt bike since its been so warm. the family's doing well, thanks for asking. palmer likes making vroom vroom noises and sitting on the bike already.
She's a Cutie Blake!!!! Gonna make a Motorcycle Rider out of her? How's the GS doing? ANy more cleaning secrets? Boojum!
Rob, I could come over from Joplin this evening and take the problem off your hands to relieve you of further worries. GS Tom
Mmmmm, let me think.......not yet. The PD always gives me the grins. Except when stuff happens and I have to get the wrench out of the sock drawer. Plus it is so big that I have problems with getting on to the smaller nuts and bolts. Thanks though. Rob
