I appreciate any advice, poor idle and

[GS4504me]

Trying to get my bike to run right! I just bought the bike. Previous owner just rode the bike up from california, I live in washington. The owner said it ran great until he got up here. He pointed out that it had a stumble at about 2500- 3500 rpms. I rode the bike home which was down the hill and around the corner pretty much.
The compression was 155 on both cylinders when the bike was cold.
Went through the carbs, dipped everything, checked for any issues, found none.
Checked the intake boots, doesn't look like there are any tears, replaced the o-rings with some from where I work (unsure of material). I just pulled the off again to look for leaks (tried the starting fluid trick and it was hard to tell if it was just getting a little in the air filter, but there was a few rpm jumps when I sprayed the boots.

As far as I can tell spark is good to both cylinders, maybe I should inspect the wiring a little bit more.

I believe the filters on the bike are K&N 60mm round cone, and i believe the BS34 call for a 51mm, it seems like there could be a small leak around the base of the filter, but I don't think that this is the case.

Anyway. I'm trying to track this down "smart" instead of "hard". I don't want to trouble shoot myself crazy and I really don't have a lot of experience with motorcycles, More car experience than anything.

Any advice on jetting, I live by the water in washington state.... bike has cone filters, and harley straight pipes. I noticed a tiny exhaust leak on one cylinder that goes away when it warms up. I'm ordering a new gasket.

Now I'm rambling, Thank you for any advice. It doesn't want to idle great, and stumbles between about 2500-3500 rpm and then pulls hard from there. I have been reading tons of other forums, and just need a budge in the right direction or directions.

 

[Guest]

If the intake boots on the head are original, then they are likely hard, shrunken and won't seal well no matter what. How hard is it to get the carbs in them? If it's more effort than a little shove to get them to slip smoothly in, then replace them.

 

[tom203]

"It doesn't want to idle great, and stumbles between about 2500-3500 rpm and then pulls hard from there. "

It sounds like intake leak.Like pete said, those old boots might be hard to lace up after being disturbed. Better check on material used in those head interface o-rings;ordinary plumbing o-rings (buna) won't survive long at 300 degrees- you need viton ones.

 

[GS4504me]

It takes a pretty good push to get the carbs into those boots. I do one side at a time and give it a good push. They look like original boots, not in bad shape but some light cracking and the plates aren't flat. Putting them face to face reveals quite the curvature in the metal plates. I found some oem ones on ebay with o-rings and gaskets. Im ordering a new set. I'd rather KNOW they are not the issue than trouble shooting just to replace them later on. I forgot to add, when I pulled off the boots this time, the o-rings were ready to "get out". They were to big because they expanded significantly. Ill fix this issue and go from their. Ill also open the carbs once more to verify what jetting is set at.

 

[BassCliff]

Greetings and Salutations!!

Greetings and Salutations!!

Hi Mr. GS4504me,

Go through ALL of the maintenance steps in the "mega-welcome". Skipping steps or taking shortcuts will lead to frustration at best, carnage at worst.

If you are here you probably have a 30 year old motorcycle that needs about 20 years worth of maintenance. In the links below you'll find maintenance lists, documentation, wiring diagrams, "how to" guides, vendor links, tips, tricks, and a whole lot of GS goodness. This is your "mega-welcome". Let's get started.

Let me dump a TON of information on you and share some GS lovin'.

I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", "Top 15 Tips For GS Happiness", the Carb Cleanup Series, and the Stator Papers. All of these tasks must be addressed in order to have a safe, reliable machine. This is what NOT to do: Top 10 Newbie Mistakes. Now let me roll out the welcome mat for you...

Please Click Here For Your Mega-Welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

More links to helpful threads in the forum:
Help! Your Bike Won't Start
DON'T DO THESE THINGS
Help! Your Bike Won't Run Well
Oh God! Pods!


Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

 

[Guest]

Cool, I thought my boots were ok at first but I had to use rubber grease to get the carbs in easily.

After buying new ones, the different was incredible, the carbs slip in very easily and with the new O rings from www.cycleorings.com they seal spot on, no intake leaks.

 

[rustybronco]

Trying to get my bike to run right!

I just bought the bike. Previous owner just rode the bike up from california,

The owner said it ran great until he got up here.

bike has cone filters, and harley straight pipes.

What's wrong with this picture?

 

[ThrottleBack]

How drastic is the elevation change? Could just be a tune issue which would support the sellers statement.

 

[rustybronco]

The bike has CV carbs on it.

 

[GS4504me]

My guess is elevation is close to the same however I cant confirm that. he lived relatively close to the water but that doesn't say much about elevation. As far as I can tell that are BS34 carbs. The main jet and pilot jet are housed in the bowl. I believe that is a BS34. Any way. I have brand new oem boots and gaskets showing up today. If it doesn't Idle better after this I'll know that my boots weren't the problem. appreciate the input, I don't think it is just the elevation change, I kind of think it is a vacuum leak issue

 

[tkent02]

The elevation change won't matter at all with CV carburetors, at least it wouldn't with properly tuned ones. They compensate very well for air pressure changes. What they don't compensate for is changes in intake and exhaust. Those K&N filters will allow more air to pass than the stock air box, while the Herdly exhausts will pass less exhaust than stock. A very difficult situation to tune for. At least on my 650 the Herdly pipes are VERY restrictive. I bet your problem is a jetting one, as anyone who knows how to tune these bikes would never use this bad combination.

Go find a decent 2-1 pipe and start tuning.

 

[tkent02]

How drastic is the elevation change? Could just be a tune issue which would support the sellers statement.

More bad info from an instant expert who knows nothing. His bike has CV carbs, which compensate for elevation.

 

[ThrottleBack]

More bad info from an instant expert who knows nothing. His bike has CV carbs, which compensate for elevation.

It's my understanding from reading here that the CV carbs can adjust, to an extent (research seems to suggest a change of more then 2300-2500 feet requires jetting) based on air flow and not air density. So on a ride into slightly higher elevations you are likely using more throttle anyway aiding the carbs in adjusting. Since the slide operates on vacuum differences in barometric pressure should affect the slide to an extent, but the carb is still regulated based on jets so at some point the elevation can over come compensation.

I'm no expert I won't claim to be. I am simply suggesting the possibility of elevation issues based on information I am absorbing on this very website. If my understanding is wrong then I am glad you can point it out and hopeful that you can educate me.

 

[tkent02]

It's my understanding from reading here that the CV carbs can adjust, to an extent (research seems to suggest a change of more then 2300-2500 feet requires jetting) based on air flow and not air density. So on a ride into slightly higher elevations you are likely using more throttle anyway aiding the carbs in adjusting. Since the slide operates on vacuum differences in barometric pressure should affect the slide to an extent, but the carb is still regulated based on jets so at some point the elevation can over come compensation.

I'm no expert I won't claim to be. I am simply suggesting the possibility of elevation issues based on information I am absorbing on this very website. If my understanding is wrong then I am glad you can point it out and hopeful that you can educate me.

OK, VM or other non CV carbs, 3,000 to 4,000 foot range at best where they run well. I tuned my 750/1000 to be slightly lean at 6,000 feet where I live, had to go easy on the power not to blue a pipe or burn a valve down here. It ran great from 7,000 to about 8,500, above 9,000 you had to start feathering the throttle, less throttle as elevation went up. Above 10,000 you couldn't open the throttle much at all or it would bog out. Same with my DR441, it's lean at home, gets better as you go up to 8,000 or so, then gets too rich. At 12,000 feet it runs, but not real well. It does do better up high than the VM equipped GSes did.
Now I have switched to mostly all CV bikes, or FI. When riding CV equipped bikes jetted for sea level up to 14,000 ft, they run fine. They lose a bit of power of course but the mixture is right, plugs look right, no problems at all, ever. It compensates very well indeed.

 

[ThrottleBack]

Thank you for that. I wonder if those providing the information I was going off of were speaking purely from their chair. On the road experience is hard to argue with.

 

[GS4504me]

Thank you. ordered some new OEM boots with proper gaskets and 0-rings. bike runs much better, and idles very well. I believe I might need to play with the jets to get it just right and possibly go through the carbs again and verify that everything is set relatively close to factory specs, but I am at a point where I can start riding the bike and getting it dialed in. Thanks for the advice. I appreciate it. I live down at the marina and work at a marine supply shop. I was in the parking lot putting it back together and a regular customer stopped and got talking to me, he is building a custom cafe bike with the same engine so I found someone's brain to pick . Its not about what you know, but who you know.