Running rough when hot... Help please

[zippo6]

I'm not sure where to start.... with the symptoms perhaps.

Once the bike is at what I will call the 'normal operating temperature' or about half way on the temp gauge, I experience the following:

• Idle drops below 1K, not much mind you, kinda jumps from 900-950?. However if I blip the throttle, it'll come back to about 1100(normally), then slowly goes back down to 900-950'ish <-- this will take about 5-10seconds.
• If I try to roll off from a dead stop without blipping the throttle to bring the RPM's up, it will bog down (Mis-fire?). Even at this point I sometimes need to clutch it and crack the throttle to bring the rpm's up once I begin rolling. After I clear, say 2K rpm, it's fine.
• Shifting... shifting gets stiffer when the bike is hot and these other symptoms flare up. Finding neautral is challenging at best and almost impossible to find from 1st, I find that I need to get her up into second then I can usually pop her down into neautral.

So here is what I have done so far:

• Changed oil and filter when I bought it (I 'might' have 1500km's on it, Yamalube 20W50 and Yamaha Filter)
• Flushed Clutch line with fresh DOT4
• Replaced NASTY fuel filter (I'd swear it was original!)
• Changed Rear Gear Oil.

I still have to change the plugs, Parts store screwed the conversion and gave me the wrong damn plugs....

I'm 100% sure my carbs are out of synch.... but I don't have a synch tool so I think I'll order one. In the mean time, would it be worthwhile to try cleaning the carbs? Or should I wait till I have the synch tool so that they can be synched once I put them back on?


I'm open to all suggestions, I'm new to the Vmax and I plan to have her a VERY long time! So I certainly want to keep her maintained. It's just the knowledge I'm lacking. :ummm:

 

[Hatter]

I'd run some Seafoam though it is the very first thing I'd do. Start with the simple stuff first.

 

[zippo6]

I'd run some Seafoam though it is the very first thing I'd do. Start with the simple stuff first.

Crap, I forgot to mention that. Current tank of gas has SeaFoam in it. I've been able to burn through less than half of it so far. Since replacing the fuel filter, bike IS running smoother, but far from perfect.

 

[Hatter]

Run 2 tanks of it. Seafoam works good but it can take a few tanks if the system is really dirty.

 

[zippo6]

Run 2 tanks of it. Seafoam works good but it can take a few tanks if the system is really dirty.

Given that the fuel filter I pulled out was the color of aluminum (yes, it was plastic) and has multiple surface cracks, I suspect it is dirty!

Thanks for the advice, I'll continue to ride so I can run the SeaFoam through her. She's still running strong, lifted the front tire for me last night!! (ya, it was my first)

 

[gamorg02]

seafoam idea before u crack carbs is a good idea.

carb synch is a good idea too. i got a $25 carb synch tool (not great but gets the job done)

mine gets a little finicky when really warm to as far as shifting, nothing ever to worry about in my mind

as far as finding neutral, if u blip the throttle does that help? it always helps me