Odd behavior at idle.

Hello all. First time street bike owner here, looking for a bit of input.

I just recently picked up a 2004 VFR800 and am really loving the bike so far... However, I've noticed that on start up, shortly after the bike starts to register a temp reading, it will shoot its self up to about 4k RPM and just pin its self there! Generally kicking it out of neutral and getting it rolling will calm it down, but left sitting for more than about three minutes it will do it again. I can't imagine this is normal behavior, and was just looking for some opinions!
Thanks in advance!

 

Sounds like the Fast idle Wax Unit might be having issues, check out belows youtube it may help.

[video=youtube;k4oVVbzTvVo]http://www.youtube.com/watch?v=k4oVVbzTvVo[/video]

 

Hmm, I will check that out and see if its been tampered with, or has any obvious flaws. I'm not sure what possible malfunction could cause that piece to further expand AFTER the bike is up to temperature... But It's certainly worth a look.
Would it be possible to actually start the bike and watch it working with the tank up and air box off?

 

My gen 5 mk1 has a manual fast idle so unsure, hopefully someone here knows or search here or that other vfr site vfrdiscussion for a similar problem.

 

+1 on the fast idle wax unit. Google "VFR800 fast idle wax" for more info.

 

G'Day nacho

I've had the same issue on my 02. Fixed now. I believe it was caused by air in the system. It has taken me months to sort the cooling system out. There was lots of "furry" calcium, mineral stuff around connections that I reckon was letting air in, but not leaking fluid out of. I have a heap of pics showing green gunge in the thermostat and housing. The little return line in the thermostat housing (from the rh rad) was blocked also.
I suggest bleeding the system on the side stand first, if that works for a short time only....you should pull the throttle body and check out the thermo housing and all other connections.

Is the bike dumping coolant out of the overflow tube (onto the ground/back tyre)?? If so this indicates air leaching into the system. It is trying to pressurise, but can't.

Hope this helps, good luck...
Cheers fron Aussie land

 

Great info! Mines been doing the same thing since last fall. Appreciate the info! I'll look into this further