VM24's too rich

SATXpipe

New Member
Hey, I have a set of new VM24's on my CL360 and they seem to be fouling plugs even at idle. I have a cheap set of pods on there and shorty exhaust, just running stock carb jet sizes. I've adjusted everything as much as possible and still running way too rich so I think I need to start subbing jets out. Does anyone know where I could get a kit with all smaller jets to try out? Or maybe someone can point me in the right direction for jet sizes for a comparable setup on the 350/60? Thanks!
 

teazer

Over 10,000 Posts
DTT BOTM WINNER
When you say "stock sized jets" do you mean the same number Mikuni jets as the were in the OEM carbs or something else? Keihin jets are not numbered in a similar way to Mikuni VM jets. If it's rick at idle, open the air screws up until it runs cleanly. If that takes more than say 2.5 turns out from fully seated you need smaller pilot jets. Get idle and just above idle first.
 

ex119x

Been Around the Block
I have questions whether the vm24 is even close to being big enough for a 360. General consensus is that the 350/360 needs to have 28 to 30 mm slide needle carbs. I have not heard of anyone going as small as a 24 on one. I also doubt that there are jetting specs for a 24 on a 360, so wonder if a generic VM24 is even set up for a 4 stroke rather than a 2 stroke application. You may end up chasing your tail on this one. All that being said, I would follow Teazers advice to get the idle somewhat close so you can continue tuning with a running engine. I generally like to go after the main jet first, then the needle and finally fine tune the pilot.
 

teazer

Over 10,000 Posts
DTT BOTM WINNER
I follow the same approach but I like to get idle in the ball park first or it's too freakin' hard to start and ride. Then Main jet. Absolutely.

The old CL350 came with a pair of 24mm Keihins (or was it the SL350) which would flow slightly less than a pair of 24mm Mikunis, but you are right, tehy are a bit small. We ran Keihin PW26 on our 175cc CB160 and VM28s on our 240cc CB160, and that was based on flow analysis and velocity for the revs we needed to run at.

For running around town 24s might work. They do sound a bits small, but that's what he's got.
 

cxman

Over 1,000 Posts
DTT SUPPORTER
are your pods clear bore or do they reduce the intake size? even further
24s are small so will run rich at high rpms due to aperture size if you have venturi restricting pods it will be like driving with the choke on
 

SATXpipe

New Member
The bike starts on the first kick, idles, and runs, the problem is it fouls plugs very quickly. The pods don't reduce down further, same size as the carbs. The jets are the same jets that shipped with the VM24's new, I haven't modified them. I was given this set of carbs for free and I'm trying to make the most of them. I've adjusted the carbs as much as I can and while everything "works" I cant get but about 10 miles out of it before the plugs are too fouled to run anymore. When I install new plugs and start it up, even at idle the plugs are pretty black after a few mins so I'm trying to jet down idle first, then move on to the rest of the jets if needed. When running the only issue of note is a slight lag in acceleration if gunned quickly. I was planning to address that after lol.
 

cxman

Over 1,000 Posts
DTT SUPPORTER
Standard VM24 Setting: 210 main, 40 pilot, 864 N-8 needle jet, 5I1 jet needle, 1.5 slide

so first the slide is to small and will cause problems pilot and main are to large even with say a 2.5 slide

why do you not just sell them and get what you need ? even when you get these to idle that are still to small
 

idahofrank

New Member
Saxtpipe, Something just hit me. I saw it once years ago. I am old and can't remember which carbs/bike it was, but the slides could be reversed (left slide into right carb and right slide into left carb). The owner didn't realize the cutaway was facing the engine side. He brought it into the shop complaining about running very rich. It was an easy fix.

It is a long shot but it will only take a few seconds to confirm.
 

DTT Bike Of The Month Gallery

DTT Light or Dark

www.jadusmotorcycleparts.com
www.cognitomoto.com
https://www.townmoto.com
www.speedmotoco.com
www.lostapostle.ca/
www.sparckmoto.com
Top Bottom