rxs100 revs high then loses power and cuts out

[jamierxs100]

Hi,

just bought an rxs100, my first bike. Rode it home about 30 miles, and loved it. On the right turn into my street it cut out and I had to push it the rest of way.

When I try to start it in neutral its revs by its self to about 6000 and then loses power and cuts out.

Could this be the battery? battery level is at minimum level exactly. the guy who had it before me only did 10 miles in the last year. the spark plug is new and oil levels look good.

any advice would be appreciated

J

[Cynic]

Nothing to do with the battery at all, it will run quite happily without one, although your lighting would be a bit dim at the lights.

You may have trapped the accellerator cable turning right, slim TBH or there is muck in the carb from standing for so long or the slide has stuck.

Give the carb a good clean and make sure all the jets are clear and you should be fine.

[jamierxs100]

doh, think I was just out of fuel!!

The who sold it me said i was fully tanked so didn't think to check . Put a tenner in an its revs at around 3000 now idle.

thanks for the help!

[Airhead]

3000 idle, sounds a bit fast? I would have thought 1500 - 1600

[tgsm7]

idle in the haynes manual says 1300 rpm +/- 50rpm

[jamierxs100]

looked at Haynes, suggests to check Carburettor top and Throttle stop screw. Looked this morning at noticed a leak from a filter that the previous owner fitted to the fuel line, looks like he used cable ties rather than the correct clamps.

[jamierxs100]

also noticed that the overflow pipe has been dripping all night, and looking at the paint work (badly bubbled) it has been dripping for a long while. Do you think the overflow drip is caused by the fuel filter leak? Is this the first thing to check?

[Airhead]

whats overflowing, the carb?

if so its more to do with float height setting or a stuck/dirty/worn float valve

[jamierxs100]

yeah, its the carb overflow. think I've now stopped the leak from the fuel filter, lot of fuel still coming from the carb overflow.

[Airhead]

sometimes you can get away with a gentle tap to the float bowl to re-seat the valve, try this to see if you are lucky it sometomes works, dont hit it with anything metallic or you will mark/damage it!

[jamierxs100]

ok, gave the float bowl a few gentle taps (with wooden object) immediately caused fuel to spill from carb overflow, guess thats to be expected. have it covered with a fresh cloth and will monitor the situation. Thanks

[jamierxs100]

looks like the gentle taps have not improved the situation

[jamierxs100]

got the revs down to 1500ish by adjusting the throttle stop screw. so that issue is sorted. thanks.

[Airhead]

looks like the gentle taps have not improved the situation

still overflowing?

[jamierxs100]

Hi Airhead, yup, still overflowing - though I think its stopped because the tank is empty. The fuel tap has a fault so is not cutting off the fuel. I'm going to try and take the tap apart tomorrow before I buy a replacement. I've read on here that the tap has a filter, and that can work lose and cause rust and dirt to get into the carb. Maybe this is what has happened. Although there is not air filter either, and filter casing has a big hole in it.

in any case, tomorrows jobs seem to be to look at the tap and maybe take the carb apart and clean it. Sound good?

[Airhead]

a bit of a tip jamie

the fuel tap often has a bowl that unscrews, the tap material is a zinc alloy which is pretty soft and easily damaged!

If your bowl has a 10mm hexagon at the bottom to unscrew it with...***use a 6 sided socket*** not an open ended spanner or a ring spanner, I have rounded these things off on the past so I speak from experience!

[jamierxs100]

Thanks for the tip, when I looked just needed an alan key, came off pretty easily.

drained the tank, removed the tap, the filters were in place although one looked a bit bent. Opened up the tap and saw the issue, the rubber inside has a deep groove that causes a permanent connection between the reserve inlet and the outlet to the carb.

will order a new one from yambits. While I'm at it thought I should order a new float bowl gasket, but not sure which one will fit the rxs100. The only think on there is the whole Carb kit which I don't want to buy just yet. Just want the gasket. Any ideas?

J

[jamierxs100]

ok, emailed yambits about float bowl gasket and ordered fuel tap anyway. Also ordered an in-line filter (from amazon).

took the carb out and cleaned it a carb cleaner and compressed air. looking pretty foxy now. was rust and dirt in the float bowl. Also noticed the outside of the bowl looks to have cracks, but these don't seem to go all the way through.

the elements I removed were the gasket, pivot pin, float, needle and seat. Cannot see any issue with pin and everything looks unworn.

Needle Jet and Pilot Jet are now clear and I can see light through them. Everything has had a thorough clean and air blast.

measured float height with carb on its side, so that float was touching the pin but not depressing it's spring. Using a school ruler it looks to me like the float height is 19mm. Haynes says 21 +-1mm. So I think my float height is out by 1mm maybe.

not sure how to adjust the float height on this bike though, the only thing I can think to do is adjust the seat, but this is already only just tight enough, if I slacken it off it will raise the float but be too lose.

[Airhead]

you adjust the float height by bending the tang slightly...the bit thet presses on the float valve.

while the float is out give it a shake to make sure there is no fuel in any of the floats

[jamierxs100]

the tang is plastics, the float and tang look like one bit of plastic. Bit sacred to bend it as I'm worried it will snap.

the floats are dry, no issues there I think.

cheers