Major power loss

[maniaka]

Hi there

the bikes been sitting for about 2 months (with very occasional start ups and 2 minute rides to shops)

Yesterday I started the bike up and went for a ride, was a bit down on a power and when reaching high rpms (about 70mph) it would jerk and bog violently so i slowed to a stop and it cut out, wouldn't bump but I wasn't far from home so walked it back

Today I stripped it down, found out there was water in my air box so assumed that was the cause, and cleaned the carbs (as well as I can - the previous owner stripped the bolts so I can't get to the jets and float) put it all back together and now it starts but it feels as though there is about 2 hp in it, it won't see over 40 mph and is slow to rev (even from idle).

Its not valve clearances as the bike was fine before letting it sit, the air filter is only 1000 miles old. Its got new fuel in so its not bad fuel.

Am I right assuming it must be either something to do with the feuling, or maybe i've put some of the gazillions's of tubes on the carbs back wrongly ?

Its now dark and raining so can't have a look at it until tomorrow

Many thanks, Hopefully its an easy fix

[Badot]

As far as the original problem -- did you try running the bike on prime when it started jerking around? Did you put it on prime before attempting to restart it? It sounds like you ran out of gas indicating a problem with fuel line blockage/pinching, gas cap venting, or the vacuum petcock.

With the current problem, major power loss and slow to rev means it could be running on one cylinder. Try grounding out the spark leads to the engine one at a time to see if you can confirm this. Improper hose routing can definitely cause this.

Next time you have your carbs out, get those screws out and replace them with socket head cap screws. It's fairly easy to cut a slot in them with a hacksaw blade or a dremel to use a flathead on, and many people can get them with a pair of vice grips.

[Slack]

I had to grind down my needle nose vise grips to make them a little more needle nose, but was then able to remove the stripped carb screws.  That's not something you can just ignore if your having power issues.  It sounds like something didn't get hooked back up right.

[maniaka]

The original problem wasn't due to fuel loss as It was actually on a full tank (My guess was due to the water in the airbox, whenever the engine was at high speed it would suck in some of the water causing the jerking and bogging) It did this a few times before it bogged down :/

i never thought about it running on 1 cylinder though - the spark plugs are probably about .. 1 year old ... 10,000 miles ish :/

but yeah i defiantly need to clean those jets and double check my hose routing !

[Badot]

The original problem wasn't due to fuel loss as It was actually on a full tank

2 Things hold fuel. The tank, and the carburetor float bowls. Just because there's gas in the tank doesn't mean there's gas in the carbs.

[maniaka]

touche

I drained the float bowls earlier today before I took the carbs off and they had feul in so i can only assume fuel was getting to the carbs.

[Slack]

I've pinched the fuel line before trying to get the damn stock air box back in and had plenty of juice around town but would hit a wall on the highway.

[weedahoe]

If it were me, I would pull the carbs, clean them thoroughly and try to synch them. Then I would check plugs and valves

[maniaka]

FIXED!



I forgot to put one of the spark plug caps back on   

puuurrrs like a kitten now

Thanks for all the suggestions non the less

p.s. will still get the screws for the carbs sorted

[Janx101]

good its fixed...

i was just about to say .. you lost major power(s) ?!?! ...

found him!!