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jonacol
17-05-05, 08:49 AM
Got a minor niggle with my '01 Sv. When reapplying the throttle after slowing for corner entry its very difficult to open the throttle smoothly without a sudden slight jerk. Not a big deal, just wondered if there was a known fix for it. Engine is standard apart from Quill T3 can.
ta
JonC

Mogs
17-05-05, 09:16 AM
Your chain maybe too loose!

Scoobs
17-05-05, 09:19 AM
It's the character of the engine. Try to NOT completely close the throttle in the corner. It is normally when going from a fully closed throttle back onto the gas when the bike gets a bit jerky.

Sid Squid
17-05-05, 11:26 AM
Also a symptom of out-of-balance carbs/throttles, depending on whether you have an early or late bike.

jonacol
17-05-05, 12:10 PM
Thanks for the prompt reply's men. I'll check the chain, usually fairl good with that sort of thing, tho'. Is there a carb balancing 'how to' tucked away somewhere you can point me to? I've done it on my old firestorms and it wasn't too bad, but a few pointers may save me time and agro (I haven't got a manwal for it yet).
cheers
JonC

embee
18-05-05, 06:07 PM
If everything's spot on, there should be no appreciable stutter or jerkiness when "tipping in" from overrun.

I'd suggest first balance the carbs. Most people fit a short piece of pipe permanently to the front carb stub because it's a bit of a pain to get to where it is. Use the original blanking cap on a short piece of tube fitted into the new pipe (appropriate sizes obviously).
The rear carb is easy to get to, use the tapping that goes to the tank vacuum tap (ideally fit a temporary T-piece to keep the tap working while doing it).

It's worth draining the carbs first, they do tend to collect bits of crud and maybe even small amounts of water from condensation. With the airbox off it's reasonably easy to get an allen key into the drain screws in the side of the float bowls (usual thing, crack them open a turn or so and the fuel drains out of a stub in the bottom).

Tip-in stutter is as often as not due to weak idle mixture. You really need to clean the carbs thoroughly, removing the idle screws and blowing through the passages, then reset the idle screws to 2 1/2 turns out (for a start). The idle screws are difficult to get to in situ, not impossible but difficult.

I also recommend iridium plugs since they do extend the lean limit for ignitability, so will help make the engine more tolerant of lean idle mixtures.

Also try setting the idle speed at 1400rpm, since this gives slightly less abrupt change when cracking the throttle open from overrun.

Scoobs
18-05-05, 08:39 PM
I'd suggest first balance the carbs. Most people fit a short piece of pipe permanently to the front carb stub because it's a bit of a pain to get to where it is. Use the original blanking cap on a short piece of tube fitted into the new pipe (appropriate sizes obviously).

I did this, but I split the original cap trying to prise it off the carb. Any old bit of toot stuffed up the end on the tube will be fine as long as it doesn't leek. I have a plastic number plate screw with a bit of PTFE tape wrapped round it stuffed in the end of the pipe.