Stinking Rich.

[kalbo]

I'm not unfortunately, but my bike is. I noticed that my '86 smelled a little rich at idle. I decided to turn in the air/fuel mix screws to lean it out a little. I turned them all the way in and immediately noticed that on three of the carbs there was little effect, it still continued to run on all cylinders. Only the front left cylinder was effected. I also noticed that the front right and the left rear carbs were a little wet, where the rubber carburetor manifold is attached to the motor. As though it was overflowing? It wasn't bad, but just looked like a gas leak? The bike runs at full power and idles fine. It just smells rich. I've set the a/f screws at 2 turns out, but it seems as though it makes little difference to the running rich problem. Any suggestions. Please keep your suggestions to a level suitable for a not very mechanically minded idiot. I'm hoping for an easy fix, as I don't have a lot of money to throw at a mechanic!

 

[davesax36]

I'd just send them to Dannymax, man. It'll be WAY cheaper than any mechanic near you, will be done right, tested (sometimes with video for you), and shipped back fast.

 

[Donny Daughtry]

Angeles City is in the Philippines.:ummm:
It sounds like you may have cracked intakes.:bang head:

 

[davesax36]

oh. Nevermind. Don't send them to danny.

 

[dannymax]

A common problem is floats set too rich, but there are several other possibilities. Unfortunately a rough calculation of the postal charges is $113 to get them here....pretty steep! :bang head:

 

[kalbo]

yeah...way too expensive to send them and get them back here to the Philippines. I'll get a local mechanic to check the floats. Fingers crossed, that would be an easy fix. Mechanics here are not like in the U.S. They don't have the experience of working on bikes like this, or the tools to do the job.

 

[sdt354]

yeah...way too expensive to send them and get them back here to the Philippines. I'll get a local mechanic to check the floats. Fingers crossed, that would be an easy fix. Mechanics here are not like in the U.S. They don't have the experience of working on bikes like this, or the tools to do the job.

Careful, make sure the local guy knows how to wet check the float levels. And sync the carbs when done. Checking the levels isn't hard. Plenty of threads here on this.
Out of sync carbs can make A/F screws seem unresponsive. I'm thinking you might need a carb redo.

 

[caseyjones955]

I had that with both my Venture and Vmax, setting floats seemed to help a bit. On my Vmax I had to lean out the jetting quite a bit because someone had gone and installed a DJ stage 1 jet kit which seems to exacerbate a rich problem. On my Venture setting the float and rejuvenating the jet block plugs solved the problem. Of course there are other things it could be, assuming as mentioned above the carbs are synched up.

http://www.factorypro.com/Prod_Pages/prody11.html

 

[kalbo]

We figured out that the fuel leaks on 2 of the carbs was coming from the drain screw, as the 'o' rings were worn out. We changed the 'o' rings on all four and this stopped the leak. When I got the bike it had a modified exhaust system and it appears that the carbs were re-jetted to compensate. I replaced the exhaust with an original one, so the running rich is probably as a result of the re-jetting. We haven't got around to physically checking the jets to confirm this, but if someone knows what size 'stock' jets are we'll know if they've been replaced. Thanks

 

[Donny Daughtry]

We figured out that the fuel leaks on 2 of the carbs was coming from the drain screw, as the 'o' rings were worn out. We changed the 'o' rings on all four and this stopped the leak. When I got the bike it had a modified exhaust system and it appears that the carbs were re-jetted to compensate. I replaced the exhaust with an original one, so the running rich is probably as a result of the re-jetting. We haven't got around to physically checking the jets to confirm this, but if someone knows what size 'stock' jets are we'll know if they've been replaced. Thanks

Stock mains are 152.5 mikuni-:clapping:
Air would be 170-under the slide
paj would 90 if not California model otherwise that one is 100.

 

[Donny Daughtry]

Stock mains for UK models are 150 mikuni.

 

[kalbo]

Thanks for the info. I'm checking to see if I an get the right 152.5 jets locally.

 

[caseyjones955]

Im guessing that 150s would work better. I have never tuned one with stock exhaust but have read over and over about how they are a touch rich from the factory and the Vmax likes to border on the lean side.

 

[Traumahawk]

Im guessing that 150s would work better. I have never tuned one with stock exhaust but have read over and over about how they are a touch rich from the factory and the Vmax likes to border on the lean side.

150's would work better, because the Vmax was slightly rich from the factory with 152's

 

[Donny Daughtry]

Some manuals even show some models as having 152.5 in the rear and 150 in the front-
Your main jet will depend mostly on your altitude---:clapping:

 

[kalbo]

OK. I've always found that rear cylinders do run a little hotter than the front cylinders anyway, due to their position. So keeping the rear cylinders a little richer does make sense. I need to order the jets this week. Is the census of opinion that I use 152.5 in the rear and 150 in the front, OR 150 in all carbs?
Thanks.

 

[Traumahawk]

I would run 150's all the way around.

 

[sdt354]

I would run 150's all the way around.

+1. Carburetors are always a compromise. Tune for a hot summer day and you'll be a bit lean in colder weather. but our carbs, work well too. Sync is big, as is float levels.