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cheesey
08-01-2011, 10:55 PM
Small block cold starting.
Is it normally such a pain ?
My bike takes ages to start, then idles fine for a short time, then starts stalling and generally running rough.
After about half a mile it's fine though and runs sweetly once it's warmed up.
It never used to be like this.
It's just started happening.
I've had a good look around and can't see anything obvious.
The only thing I've done recently was to change the fuel tank, but that was very straightforward.
Any thoughts ?

RossGuzzi
08-02-2011, 04:41 AM
Blocked fuel. New tank had crap init?

Check for water in the float bowls of the carbs too. Give them a good clean and try again.

pete roper
08-02-2011, 06:51 AM
I believe its a V7 Racer so no carbs Ross.

This seems to be a recurring issue with many late model SB owners. I have had no experience with it first hand and I live somewhere where it gets really cold at this time of year but a couple of things to ponder.

Firstly the ECU won't go into closed loop until the ambient temperature is >20*C, As detected in the airbox which will get heat from cylinders etc.) and engine temp rises >30*C. Fooling the ATS with a resistor is one way of helping the situation.

Secondly, check the fast idle cam. These rarely come adjusted right from the factory. there are in fact two 'Detentes' on the cam. The mechanism should be adjusted such that when the lever on the handlebar is fully depressed it engages to the second detente. The bike should then start pretty much instantly with zero throttle input, (If its tuned correctly.) once it has started it should idle about 2.7K or so. after a few seconds it should be possible to knock it back to the first detente position which should maintain the idle @ about 1,500-1,600RPM until the CL parameters have been met. At that point the fast idle can be rolled off completely.

Obviously if the bike has been incorrectly set up or maintained? All bets are off. Best baseline is always achieved with a full tune-up with Valve lash, TB sync and TPS check. Inless those are known to be correct you're essentially just wasting time.

Pete

shekel
08-02-2011, 06:55 AM
Hey Cheesey is yours a new small block or an old one? My wife's '09 V7C has done about 15000km and has always been hard to start when cold. The so-called 'cold start' lever does not seem to make any difference, and when it does fire it has to be gently coaxed to a steady idle before riding off - can be a real PITA. When warm there is no such problem - starts quickly first time. Tomorrow it goes back to the workshop under warranty for a few bits and bobs, including trying to sort the cold start issue.

If its any consolation I must have read 3 or 4 test articles on the different V7 variants and all cite difficulty in cold starting as being a minor irritant to an otherwise very fun bike. Anyone else?

shekel
08-02-2011, 07:18 AM
Thanks for your analysis Pete. There no longer appears to be any 'detentes' felt when using the cold start lever, and the bike has been idling too high when warm lately, leading me to guess that that the idle speed may be permanently stuck on the cold start setting. Anyway, your words will give us a place to start when dealing with the mechanic at Brisbane Aprilia tomorrow. When the problem is fixed I'll post findings here.:cheers:

pete roper
08-03-2011, 04:13 AM
I theink sean is there now, I was with him in Sydney today, we actually went through all of this and its actually quite simple and intuitive when you notice the extra screw!!!! :D

Pete

shekel
08-03-2011, 07:02 AM
Yep Sean's the boy alright - glad he will be full bottle on this now. I believe he will be back up at the end of the week. Hope you are all having fun and learning heaps on your Sydney training course. Meanwhile I've got some LV GPs to fit on the Shiver.:burnout:

cheesey
08-04-2011, 04:47 PM
Hey Cheesey is yours a new small block or an old one? My wife's '09 V7C has done about 15000km and has always been hard to start when cold. The so-called 'cold start' lever does not seem to make any difference

Mines a new one.
As regardsthe choke.
All the lever does is fractionally hold open the throttle.
I noticed on mine that the throttle stop activated by the lever, was about 4mm clear of the throttle, (it should actually be resting on it) meaning that pulling the choke lever didn't actually do anything.
The thing is that this has just started happening.
Up till recently it's always started instantly from cold with no throttle, and it always ran cleanly thereafter.
Today I lifted the tank to make sure the fuel lines were not snagged even though I knew they wouldn't be as if that were the case the bike would run rough all the time.
Thanks for all the input

pete roper
08-04-2011, 05:19 PM
The cable may of slipped through its nipple. Start from scratch and adjust the cable and then the cam adjuster.

Pete