Questions from a newbie

[usin13]

Gas?

umm..are you out of gas?

I was hoping that was the problem when it was happening but no, there is plenty of gas.

[rustybronco]

No offense was meant to the multiple carbs. My entire mechanical knowledge stems from that 1961 ford Falcon, so I couldn't tell you about triumph or anything else. What is different to me is the way the engine sits. On my falcon, the carb sits right on top with a gasket. 6 cylinders use one carb where on the Suzuki each cylinder has a carb. Just completely different from what I know. You should have seen me debate the best way to check spark. I was worried that if I did it with the electric start, it would just start on the other 3 cylinders, and not knowing what kind of affect that would have on the engine. So, I have not yet checked the spark.

NO offence was even thought i was just saying... they are one in the same as someone said suck squeeze bang blow.

[usin13]

Update

This morning I went and started the cycle. It started like normal. I did full choke and slowly backed off the choke. Also like usual I can only get the choke about 1/3 of the way open. I drove it to work, which is about 30 minutes, with no issues. Unfortunately, I still have some gas leaking. Not as much as I did when the petcock was on prime, but still getting some. I think however I am going to start by replacing the intake boot o rings to address the sporadic RPM. After I do that, I will look at the leak. One thing at a time I suppose. I assume it is best to just get a solid idle first and then start working on the other issues. Is that correct?

[bwringer]

It's a VERY bad idea to continue riding a bike with possible intake leak or any lean running issues -- it can quickly overheat the engine and lead to some pretty gruesome engine damage.

I'd post photos of the horrible remains of my bike's original exhaust valves (damaged by intake leaks), but they're just too graphic for a family forum...

[chef1366]

Take off your fuel line going to the petcock and put a temp one running to a bucket or something. Pull the vacuum line off the bike but leave it on the petcock. Suck on the vacuum line on Prime and it should run even when you remove vacuum. On run the petcock should only spew gas with vacuum applied to the line. If you get a mouth full of gas rebuild time. If you don't have good flow, rebuild time. You also need to check your float needle and seats because they are not shutting off gas flow.

[usin13]

It's a VERY bad idea to continue riding a bike with possible intake leak or any lean running issues -- it can quickly overheat the engine and lead to some pretty gruesome engine damage.

I'd post photos of the horrible remains of my bike's original exhaust valves (damaged by intake leaks), but they're just too graphic for a family forum...

Never fear, I bought some o rings today and tomorrow night I will start to put them in. Be prepared for more questions when I start that. :-D

[usin13]

Thanks for that info. I will do that either tomorrow or Friday as I replace the o rings. Do you think doing it before the o rings, or after is better?

[usin13]

Update

Tonight I took off my gas tank, air filter assembly, and carbs so I could get to my intake boots. The first bolt I tried came off no problem so I thought I was golden. After that, I only got one more bolt off, so tomorrow it's to the store to get an impact wrench. When I couldn't get more bolts off I took a look at the petcock. I turned it to On, sucked a little on the vacuum hose and got a nice flow out the gas line. As soon as I stopped sucking, it stopped flowing. So, I feel that my petcock is fine. I guess that leaves the carbs for the leak.

I also cleaned up the outside of the carbs. I took off the vent lines and tried to blow air through them (with my mouth, not a compressor) and one of them would not allow me to blow any are through and one would only allow a little air through. The one was completely plugged at the end and I smacked it on my workbench and the dirt fell out and I could blow through it easily. I did the same to the other one and that worked as well. Obviously I should replace them. What effect did those two vent lines being plugged have on the engine (just curious)?

I also drained the bowls and am glad to say that I got the same amount of gas out of each bowl and it was very clean, not dirt/grime.

So tomorrow I'll get the impact wrench and some hex head bolts, replace the o-rings, put it back together and keep my fingers crossed.

Thanks for all the help so far.

[usin13]

One other thing

When I got to the point on the carb where I had to remove the throttle cables, one wasn't even connected to the carb, it was just kind of sitting there. It was the one that is connected to the piece that the idle adjustment screw hits. Why are there two cables? I only had one hooked up and it seemed to be working fine, so what's the benefit of the second?

[chef1366]

If your vent tubes were clogged then this could be your problem. You can hold fluid in a straw by blocking one end, release the end and the fluid will flow. Same theory.

[usin13]

Here are the intake boots between the carbs and the engine, a common source of nasty intake leaks:

http://bwringer.com/gs/intakeorings.html

These photos and part numbers are from a GS850; your bike will look about the same if it's an early 8 valve 750, although the part numbers are different.

Ok, the hand impact wrench is about the best tool I've ever used. The remaining 6 screws came out with no problem. I got the boots off. Mine look different than the ones in the link, only in the fact that I don't have synch ports like these, rather that is in the engine. Here is the biggest surprise. There wasn't 1 o ring on them. Not one. No wonder I had an intake leak. The boots are nice and pliable and I could see no visible cracks.

I'm still a little shocked to not see a single o ring.

[rustybronco]

.

I'm still a little shocked to not see a single o ring.

you should have seen the carbs on a 1,135 mile honda i'm doing, silicone rubber bowl gaskets, broken float post repair crap floating in the number 4 carb bowl NOTHING surprises me! can you say HACKS!!!!!!!

[usin13]

Success

Great news! I put on the o rings, intake books, carbs, air filter and gas tank. I put the petcock to prime to get some fuel back in the bowls. I tried to start it up like normal, with full choke. I got nervous because it wouldn't start. Turn of the choke and started right up. Turned the petcock to on, adjusted the idle and low and behold, it idles at about 1200 RPM nice and smooth. :-D I then took it for a drive. Drove a couple of blocks before my first stop sign. I pulled in the clutch and....it idled at abou 1200 RPM. Took it for a 20 minute or so ride and still no problem. I forgot to put the carb vent lines back on, but I'll do that tomorrow.

I also didn't see any gas leaking. I'll check again tomorrow as it will be on the side stand all night.

I do have one more question. It seems as though everyone has to order those o rings from their dealership. The Suzuki parts/service shop around here had them in stock. I watched them look it up by part number in the computer, so I know that he looked up the right one and they claim it is not just rubber. Should I trust them? I'm only curious because no one else's parts place seems to carry them.

Thanks again.

[beby99]

I do have one more question. It seems as though everyone has to order those o rings from their dealership. The Suzuki parts/service shop around here had them in stock. I watched them look it up by part number in the computer, so I know that he looked up the right one and they claim it is not just rubber. Should I trust them? I'm only curious because no one else's parts place seems to carry them.

Thanks again.

They should be fine. Did they come in Suzuki packaging? If not I would question them.

[usin13]

They should be fine. Did they come in Suzuki packaging? If not I would question them.

They went in back with the part number and walked out with four o rings. They claimed to keep plenty of those in stock. I guess I will keep my eyes on it and see if I start getting Idle problems. If I do, at least I know how to repair it now and I can always order a new set from Bike Bandits.