Something is heating up

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

James t

To boldly go where no man has gone before
Supporting Member
Joined
May 9, 2022
Messages
165
Reaction score
104
Hey guys I have a little problem with my 85 all original VMAX, when it gets hot the bike bogs down and quits running like the choke is on also at the very same time if I go to start it I get nothing at the starter relay, I hit the run switch and nothing no starter turnover no relay clicking if I wait 5 or 10 minutes the bike will turn over again and it will start if I go down the road about another few miles it does the same thing any thoughts you guys on where to start I'm thinking something's heating up possibly , also I'm going to rebuild my carbs again what carb kit do you recommend , and can I go larger Jets without doing any modifications
 
Last edited:
For the starter not to turn over would point to the starter/turn signal relay.

The early models have a combined unit. It can be unplugged and bypassed (I forget the wire but have posted about this elsewhere recently).

That would get you home but you lose the turn signals, no big deal if you have arms (I'm assuming hand signals are recognised in US)


Are you able to recreate the problem on your drive?
(no idea why the first part is in bold text)
 
I agree with you on the starter turn signal relay but that doesn't explain why it bogs down and dies almost like something is electrically shorting out
 
can I go larger Jets without doing any modifications
As far as that, you will probably only get worse gas mileage, and less performance. Mikuni 152.5 is usually stock in the USA spec bikes, going to 150 or 147.5 Mikuni on the main jet is often able to result in better performance. The bikes are jetted on the rich-side from the factory. Recall the Dynojet carburetor kits have a proprietary numbering system. Their #'s are larger than Mikuni #'s for the same size aperture. Use the search function to find the comparison chart, OEM vs. Dynojet sizes.

As to your starting problem I'm not an authority for that. It sounds like you have an electrical issue of some sort. I'd start by cleaning and re-installing all grounds, then all wire terminals for the circuits where symptoms appear. Check all wires for continuity along their lengths, while flexing the wires to see if you lose continuity.

The relay for that circuit, "replace with one of good known quality." That should help to tell you if things improve, that was the issue. Refer to the shop manual testing it first, if it fails, replace it. http://vmoa.net/VMX12-Service-Manual01.pdf
 
Last edited:
Okay I'm going to check and go over everything , I didn't mention in my first post that I haven't ridden the bike since about June it's been a few months I don't think that's really going to matter that much but it might
 
Well I tightened a few things cleaned a few things and everything seems to be good now no more issues, I think I had two different problems probably from sitting a starter solenoid that was stuck and maybe I just had a bunch of crap in the carburetor for sitting a few months it is all original parts so things are old thanks guys, I'd still give my left nut though for fuel injection
 
I'm not a CV carburetor expert so educate me guys I put on some shorter stage 7 diaphragm springs and it seems to be running a lot more smoother better and more power why is that, was I too rich
 
Properly synchronizing the carbs, proper fuel level (float tang adjustment, and do a wet-check), no air leaks, and a clean fuel system all work together to allow the fuel management system to function properly.
 
Back
Top