Jump to content

Jetting help PLEASE


333bbb333

Recommended Posts

Hi I know this is the wrong forum but I cant get any help in the carb forum. I need to know what jet setup to use, I am getting the bike to start 1st or 2nd kick but it will not stay running. I am at sea level, with a stock motor that has toomey t-6 pipes and the air box has been removed, I am running 2 mikuni 28mm flat slide carbs with a 280 main, and the pilots are whatever comes stock with the carbs, not sure the size of them. Also the carbs have two k&n style filters on them.

Link to comment
Share on other sites

we need to know what the pilot is. not all of those carbs come with the same size pilots in them. pull the pilot and see what it is.

 

Is the Pilot the smaller one right next to the main, it has holes down along the shaft of it, or am I looking at the wrong part. I did not see any sizing on that piece when I removed it. Do you know what I should be running with my set up.

 

Ill explain my problem a little bit and see if that helps at all or if you can offer some insight. I just rebuilt engine and she fires up 1st - 2nd kick and sounds fine, purring, but then cuts right off after a second or two, if I let her sit for a second she will fire right up again, and on and on. I can only assume its my jetting, the lines are clear and flowing, and shes getting spark from what I can tell. My fuel line coming into the carbs are a little loose, I noticed it leaking there at the carb when I was trying to start her tonight, could that be causing the lines to loose suction and not draw in the fuel properly?

Link to comment
Share on other sites

 

Thats what I thought, I did not see any numbers when I pulled it out the other day, I will try again and see if I just overlooked it. My concern is that these are not banshee specific carbs, I was told it did not matter as long as they were the same carb, but thats why im trying to find out what a good starting point would be for the main and pilot and then Go from there.

Link to comment
Share on other sites

Im not sure if I tried to help you earlier but size in it now is critical,what happens if you hold it 1/4 or more throttle will it run.I would try 340 mains to be safe and 30 pilots.Those pilots are not easy to come by either.You would need to call SUDCO,they also sell jet kits for diffrent applications

Link to comment
Share on other sites

this dude snoop gave me this info when i first got my mikuni 28mm flats i used it for my unported motor -- slide -2.5 needle - 5L1 2nd from top - pilot 27.5 - main 340 - float height 22mm - nozzle 175 [p4] - airscrew 2 or 2.5 turns - needle seat 2.5 - i eneded up changes my needles main and slow jets to these and made a big diff im at sea level with pods also hope it helps u out

Edited by shakar
Link to comment
Share on other sites

Im not sure if I tried to help you earlier but size in it now is critical,what happens if you hold it 1/4 or more throttle will it run.I would try 340 mains to be safe and 30 pilots.Those pilots are not easy to come by either.You would need to call SUDCO,they also sell jet kits for diffrent applications

 

Ya it will not stay running long enough to see what it does at 1/4 throttle, soon as you try to give it gas it bogs out. I pulled the pilot out and did not see a number on it but im gona recheck today

Link to comment
Share on other sites

If you can get me picks of the pilots I should have extra if I have the same type mikunis have three types

Here is a pic I found online, it looks like the pilot I have, only I think my pilot has one more thread to it and seems a little closer together but it could be the close up shot that is getting me. Regardless I can not find my cable for my camera so I just used this image since it looks just like mine. My carbs are VM28-418

post-33200-12597141333779_thumb.jpg

Link to comment
Share on other sites

this dude snoop gave me this info when i first got my mikuni 28mm flats i used it for my unported motor -- slide -2.5 needle - 5L1 2nd from top - pilot 27.5 - main 340 - float height 22mm - nozzle 175 [p4] - airscrew 2 or 2.5 turns - needle seat 2.5 - i eneded up changes my needles main and slow jets to these and made a big diff im at sea level with pods also hope it helps u out

What changes did you make to your needle, just the clip adjustment or did you have to order a whole new needle?

Link to comment
Share on other sites

What changes did you make to your needle, just the clip adjustment or did you have to order a whole new needle?

when i got my carbs they had 15 pilots and a big honkin needles it would run, but not great . i wanted it to be set up right so i got the needles and jets listed above from jets r us they have the blown up pics of ur carbs too . when u look at ur jets look at the needle # also .good to know whats in there . r u sure u dont have tm and not vm carbs ?
Link to comment
Share on other sites

  • 2 weeks later...

when i got my carbs they had 15 pilots and a big honkin needles it would run, but not great . i wanted it to be set up right so i got the needles and jets listed above from jets r us they have the blown up pics of ur carbs too . when u look at ur jets look at the needle # also .good to know whats in there . r u sure u dont have tm and not vm carbs ?

As far as I know they are TM not VM, at least that is what the box says.

Link to comment
Share on other sites

Just wanted to say thank You to everyone who helped me out, I finally got her to come back to life, she still has a little bog when I put in gear and try to run but seems to rev fine when in neutral, any thoughts? otherwise she fires on first kick and idles well, need to run her a bit longer this weekend so I can check the plugs, but I also got a little squeak I hear when I rev her up, but it only occurs for a second and only when it gets back to the idle range after being reved up, I was wondering if it could be the clutch or flywheel to tight or something, Any insight? But thanks again to everyone who helped me out getting her here, shes idling thats a gold star in my book.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...