Missing problem with my vmax

[Vfast]

I have a 88 Yamaha VMAX I put slip on COBRA pipes the bite started running lean at high RPM drove it like that for a couple months and now it's missing all the time I bought a jet kit for it will that solve my problem. Any help will be appreciated thanks

 

[sdt354]

I'd hold off on the jet kit. First the issue needs to be solved. The jet kit won't be helpful unless you get a full exhaust. Many jet down with slip-ons or stock exhaust. 150's or 147.5's should do it.
A rubber boot inspection should be first. Cracks are common and can cause the condition you have. I don't believe the Cobra slip- on's are the problem.

 

[MaxMidnight]

As Steve says, you need to diagnose what is causing the miss before playing with the fueling.

Given that the motor ran fine when you first fitted the Cobra's then it is unlikely that the fueling is the problem but it could have a knock-on effect elsewhere.
If it has been running lean then check that the plugs are still in good condition. A visual check may suffice but you can't beat putting in a set of new ones.

If unsure what to look out for have a look here.

Also check the plug caps, leads and coil towers for arcing. Probably the easiest way would be to run the bike in the dark but NOT in an enclosed space.

 

[Vfast]

Thanks fellas I'll give it a good three over I'll probably be getting back a hold of you fellas pretty soon.