help with 83 Vmax

[Dennis]

I have a 83 Vmax I have been tryiing to get to run correctly and am having a few issues. Any ideas would help.
First when it sits for a few hours it is very hard to start, I can get it to fire after a few pulls on one cylinder and full choke and it dies. If I pump the throttle it will fire again and die. If I repeat this 8 times or so the motor will take off and run on both cylinders. I have tried rebuilding the fuel pump and have replaced them also. I have also went through the carbs several times and cannot find any issues. After I get it running and warm it starts with one pull. It does idle high (2800+) and when I give it half choke it idles down and runs at about 1800.

Second on out of the hole I have a small bog, engagement it at about 4200 max rpm is at 8100-8200. It runs great after the small bog. I am running stock needles in the center clip, air jet at 1/2 turn out, mains at 290(I think)

Any ideas would help

Thanks Dennis
dennisbitt@yahoo.com

[vmax-540]

Dennis
It sounds like the trottle cable is not set right and it is holding one or both carbs from returning to normal idel , that is why it revs so high. That will also cause it to start hard when cold . Also The 83s trottle cable was a little to short , and this would cause this also, if you look, the 84s and up take a differant cable ,so if you can't get the carbs to idle down try changing to the other cable.There is an esay way to tell is to see if you have some free play in the trottle cable at the trottle lever, if you don't then it could be out of adjustment or it is the cable . I hope this will help .


Jeff F.

[Dennis]

Thanks for the idea, checked the cable, and it seems to be right. There seems to be the correct amount of play in the throttle. I made some changes today, I thought the needles were set in the center there were on the bottom clip, changed them to the center which helped a little. It only has a slight bog, two sled lengths or so, then it takes off.

Does our sled seem to take a while to hit make rpm, mine will run up to just over 7k and then climb to about 81-8200. I am using a 108 comet.

The starting issue it still there, make a small hole in the air box and used some starting fluid, it fired right up.

Thanks for the help.

Dennis

[tyler440]

sounds to me like your lean, at least on bottom..... are you sure you have the right sized pilots and such... if starting fuild helps then ide say you arent getting gas

[Robin Borse]

Sounds like you are not getting enough enrichment on a cold start. Thats why it is hard to start cold ( starter fluid helps), and runs better warm ( when a leaner mixture is better). Check the free play on the starter cables. If it is too much, you won't be lifting the starter plungers enough and the cold starts will be too lean. As for your bog on acceleration, your 108 is probably the culprit. The 108 has to be set up for the vmax specifically, it sounds like it is not allowing it to reach max revs, the weights may have to be adjusted. If the standard drive belt is being used with the 108 it may be forcing the belt lower on the secondary clutch (it should ride at the top of the secondary at start) which would result in a lower ratio and bog. The two issues are probably not related. Unscrew the starter plungers and check they are connected to the cables and then adjust the freeplay. Work on one issue and then tackle the other. Go back to original clutch if possible, thats what works best.

[Dennis]

tried choke plungers all was well and they were set to specs, I will try setting them up so they open more.

As for the clutch my idea was lighter spring and lighter weights, anyone have an idea what the stock weights are (grams) Will help so I can get some lighter sets.

Thanks for the help, it is giving me some good ideas to work with. Keep em coming

These damn sleds are toooo much fun to ride!!!!!

Dennis