Ok so this problem has been getting worse over the last few months and i will do my best to describe it. I was having this problem originally where my bike was taking forever to warm up and figured it needed the valves adjusted because i was at 15,000 miles and they have never been checked. Had the valves adjusted and got the bike back and it ran just fine again. this was last summer.

The more i rode it around town though, every time, i would have to keep the choke on longer or it would die, and now I'm at about 17,500 miles and if i don't keep the choke on the bike won't stay on unless I've been riding for practically half an hour. Even if i ride on the freeway for half an hour, i get off the freeway and stop and its ok, and then it will die at the next stop i make, if that makes sense. i have adjusted the idle adjustment screw so it idles at 1500 rpm because when i am coming to a stop the RPM will dip to about 500 and unless i give it some throttle while i am coming to a stop, the bike dies. They will drop really low, but then after about 5-10 seconds, the RPM will come up. It doesn't matter if its 40 degrees out or 80, the temp doesn't seem to have an effect. My bike does have a lunchbox filter and the appropriate jetting, but i don't think that has anything to do with it. It cost 300 to have my valves worked on last time and i don't really have that money to throw around if its not actually a valve problem, but i don't know what else it could be.

I know the valves on this bike are easy but i really don't have the time to work on them. I can do basic mechanical work, i installed the aftermarket exhaust and did all the carb work and installed the R6 shock in the back, but valves are something i don't want to mess with right now if i don't have to.

Do you guys have any suggestions to what may be causing this issue? I'm happy to provide more information if you need

thanks if advance for your help

nathan

I'm guessing your pilot jets are dirty / becoming clogged. When did you change the jets, and did you change the pilot jets? 

i changed the jets maybe a year and a half ago? i installed new jets, i think i replaced them all. i bought them from buddha for when i installed my lunchbox and slip on at the same time so whatever her usually recommends.

The valves really shouldn't be that far out in the past 2500 miles, but it is a possibility. Definitely worth looking into, even if you just check the clearances. If the shop left them at the tight side of the spec, they could be out. How easily does the bike fire up when cold?

The pilot circuit is probably the smallest (diameter wise) circuit in carbs. Where are you located? Might be a good idea to plan on parking the bike for a couple days and doing some maintenance - clean out the carbs (not just the jets), valve clearances, check the mixture screws, carb sync, etc.

the bike fires up no problem, even when its 40 out. Im located in los angeles, and live in an apartment with my bike parked on the sidewalk which can make doing work tricky. I haven't ridden the bike for quite a few weeks already though. cleaning the carbs wouldn't hurt, just gotta find the time to do it. id rather it be that than the valves though. I can do carbs, i can't do the valves. thanks for the ideas!

Check cold compression, if you have cold compression and valves aren't noisy when hot your running problems aren't being caused by the valves.  Regular valve checks are important to long engine life so do check at regular intervals but they aren't your immediate problem.  Is air cleaner reasonably clean?

Quote from: skywaytripper on January 26, 2016, 12:07:41 AM
the bike fires up no problem, even when its 40 out. Im located in los angeles, and live in an apartment with my bike parked on the sidewalk which can make doing work tricky. I haven't ridden the bike for quite a few weeks already though. cleaning the carbs wouldn't hurt, just gotta find the time to do it. id rather it be that than the valves though. I can do carbs, i can't do the valves. thanks for the ideas!

A valve clearance check is easy and relatively quick. No reason not to do at least that.
My money is on the carbs though. They should be thoroughly cleaned. Pulled completely apart, carb cleaner shot through all passages, blown out with compressed air.

thanks for the help guys. The air filter shouldn't be very dirty, i cleaned it within the last thousand miles or so. I don't have any noise from the valves when the bike is warm, other than the choke problem the bike runs super smooth. I was thinking it could be the carbs. Even though i ride it quite a bit it has been at least 10 thousand miles since they have been taken apart. I will give them a thorough cleaning this friday, as well as the air filter and we will see what happens. hopefully thats all it needs, i want to ride my bike! Ive just been riding my girlfriends honda rebel 450 in the mean time though and that hasn't been such a bad replacement

Quiet valves, huh? That usually means they are out of spec...... noisy valves are happy valves.

And a Rebel 450? Pretty rare bike if I'm not mistaken.

I could be wrong, its been at least a few weeks since i have ridden the bike and i can't quite remember just how the valves sound.

yes it is, they only made it for two years, 86 and 87. This beauty was stored in a barn in the california desert for 23 years and has no rust and 5,000 miles. The tank was refinished and the carbs are being gone through right now but this thing runs like a peach, its quite a fun bike. Im surprised at how much this cruiser can lean. Its also more comfortable for two up riding than the GS is which is nice.

Who did your valve adjustment? If I had a shop do my valves I would ask for a list of clearances, shim sizes and any shims replaced. $300 also sounds like too good of a deal for a proper valve adjustment so I'm skeptical they did it by the book.

To me, your conditions sound exactly like very tight valves. My GS was having almost identical problems at similar mileage before its first valve adjustment. Every time I pulled up to a stop sign or stop light I would have to hold open the throttle or the bike would die. Once I cam to a stop the idle would return to normal. Riding with the choke on was a bandaid.

Like Big Rich said, noisy valves are happy valves. Many of us like them on the looser side of spec which makes them even noisier.

You can check the valves by pretty easy. Make sure to check them when the engine has cooled for at least a few hours. Actually changing shims is a little harder but not out of reach if you follow the hanes or clymer manual to the letter.

the valve adjustment was performed at a local honda/kawasaki/bmw motorcycle dealer. they used to be a suzuki dealer and said that they could still work on my bike. at the time i didn't think to ask for paperwork about what they found and what they did but I'm sure that i could get it.

I thought tight valves could be the issue as well, and the reason i had them worked on in the first place was because i was starting to notice that the warm up time was increasing, but i didn't think that they would go out of spec so fast after being worked on so thats why i was trying to see if you guys had any ideas as to what else it may be. and again, i haven't ridden the bike in a few weeks so i don't know about the sound of the valves. I also don't own clearance strips, but i know they can be had pretty easily. I just didn't want to tear into the valve train if i didn't have to. Ive watched the video on how to change shims and it doesnt look difficult, i just don't have time time to do that work. Im in paramedic school and free time, and funds are very limited.

this is gonna sound stupid but i have to ask it. have u got an aftermarket choke put on when i crashed i bought one and the a arrow part that says which way for chock was put on backwards and not riding for 3 months my first couple rides i was like wtf is with this but quickly found my problem. Then if not that have u recently took your chock apart and possibly put in the little triangle part backwards dont know if that would cause issues but just a hunch at this point.

Sorry for spelling and grammar i use spell check but was never good with the grammar part.

No its still the original choke but thanks for the idea! Glad you were able to figure out the issue

Thanks for all your help guys, i took the carbs off and gave everything a very thorough cleaning, and after riding and tweaking the idle jet mixture i got it running perfectly again! guess it was just my idle jets were clogged. Just ordered a sprocket and chain so once i replace that we will be in business!