SP4 not revving
 

Out for a bimble on the SP4 today, everything fine and dandy except that the bike wouldn't rev beyond about 8500 rpm. No other problems, no funny noises, water temp absolutely fine at 70-75 deg.

Anyone got any ideas?

Thanks

BC

fuel filter ?
blocked breather ?

Just an idea
 

Try twisting the throttle a bit more?

Interesting - why would a blocked fuel breather prevent the bike from revving?

I have to take care not to overfill the tank with fuel as it occasionally seeps out of the filler cap, so there may be a problem with the breather.

If the tank is not open to atmosperics and the pump is running it could cause the tank to partially vacuum. stopping the fuel from going to the fuel lines 4D

I concur with the fuel filter theory. IME a blocked breather is more likely to cause the engine to stop or splutter as it simply eventually fails to get any fuel due to the vacuum that builds in the tank.

I had something similer happen to mine, it just would not rev. I was high up in the Alps at the time. Stoped for fuel a loud hiss as I opened the cap after that It was much better. After that I left the breather off. No probs.

On a T8 the breather valve is in the pipe that comes out of the top of the tank...it's just a push fit so it would be easy to put it on frack to bunt.

Just a thought...

From the bloke who still hasn't sussed his spluttery ST

It's probably just getting a bit old... time to get a new one... I'll take that one off your hands for a nominal fee :D :D :frog: :frog:

Cheers
Martin

If the problem goes worse and worse, you may want to change the rubber hoses in the tank. I had that happening to me once on a 916, took a month to diagnose the problem. There was a tiny split in one of the hoses in the tank. I would leak fuel back in the tank. Result, not enough pressure in the injectors and fuel starvation as soon as I was opening the throttle.
p

Blue Peter badges to all who said blocked fuel filter.

10,000 rpm red line restored. My, I do love my SP's !

Thanks all.

BC

I love your SP's as well :D

Which reminds me...I still owe you some replacement black fairing bolts and 'washers', and I still owe me a set of the same in the goldy/titanium colour.

And I also owe you a token of appreciation for letting me take your bike out for hundreds of miles in the rain, bringing it home all dirty and not even washing it.

KeefyB seemed happy when I lobbed him a case of Stella by way of thanks for the loan of his Multi - funny, I never knew he drank the stuff :lol:

You on the other hand Mr Beancounter don't seem like you're afflicted with the same thirst for Stella as us other oiks, so finding something for you is difficult

Hi Jools

I've replaced the lost fairing fasteners with gold ones for the moment, until I can get some black ones (Nelly's got some I think).

So no need for you to try to track any down.

Nor any need for alcoholic compensation - I was just happy that you had a good day on the SP3.

Maybe see you when you're back from India.

BC