Top end of first gear haemorrhages?

[Staticam]

The Cagiva has been sitting for a while so I decided to take it out for a wee pootle last weekend. It started third crank, off I go. Took a nosey around a new nearby subdivision, enough of that. On the way home I gave it the beans but it went to pot, what the! So tried again, same result, it just boggs out. Backing of its ok, changing up its ok. I think it'll bog at the top of second too but that's a bit quick for the urban enviro. I didn't take it out on the open road. Just went home and shoved it back in the garage.

So...
First gear no real load, it wont go past three quarter rev range. I have no tacho but it normally happily revs higher.
It is very clattery, probably loose exhaust valve clearance. Could this be the problem?
I know what electrical HT brake-down feels like in a car, this doesn't feel like that.

I plan to tackle setting the valves then take it for a better road test.
Before I do that - does anyone here know what the problem might be?

Cheers for any ideas.

[imdying]

Change the gas.

[Staticam]

Change the gas.

Can do, but wouldn't old fuel fail cause issues under load and initial throttle?

[Staticam]

I tightened the exhaust valves (they were loose, probably could still go a bit tighter) and changed the gas. It's still got a problem. 1st, 2nd and 3rd gears wont pull at the top of their rev range, it just bogs out. Despite my earlier comment, maybe it is electrical. I changed the spark plug, no improvement. Is there a way to test the CDI unit ... or what else to do?

[Kickaha]

The Cagiva has been sitting for a while

How long is "a while" you may need to strip and clean the carbs

[Staticam]

How long is "a while" you may need to strip and clean the carbs

carbs! I wish but it's just a single banger
In this case a while means I haven't been riding it frequently, once every couple of months for the last six. The bogging out, spluttering, missing, whatever - stops as soon as the throttle is let off. Grab the the next gear and its ok, it just chugs away with all its massive torques

[bsasuper]

I've had bikes sit for 8 months, and they started fine with the old fuel, were fine around town, but just as you describe no top end.

[vifferman]

Realistically, the only thing that's changed while it was sitting around is the fuel, unless some rubber component has been gradually degrading and eventualy ended up at the point where it's kaput. My bet would be there's some varnishing of the carb components from fuel evaporation, and/or some buildup of moisture. Try draining the carb, and buy some carb cleaner or fuel system treatment (don't use too much on the basis that "more is better" as it will soot up your plug.)

[Staticam]

I've had bikes sit for 8 months, and they started fine with the old fuel, were fine around town, but just as you describe no top end.

and ... did they come right?

[Staticam]

Realistically, the only thing that's changed while it was sitting around is the fuel, unless some rubber component has been gradually degrading and eventualy ended up at the point where it's kaput. My bet would be there's some varnishing of the carb components from fuel evaporation, and/or some buildup of moisture. Try draining the carb, and buy some carb cleaner or fuel system treatment (don't use too much on the basis that "more is better" as it will soot up your plug.)

I completely emptied the gas tank and put new fuel in. This thing just idling for two minutes would probably empty the carb so I reckon clean fuel is running through. However, giving it a strip and clean it is quite doable, I'll give that a go.

Hmmm yes rubber components - one of the fork seals has gone, though not from sitting. And the valve(s) for the rear brake master have failed

[paturoa]

When you changed the gas did you drain the float bowl? Water will sit in the bottom of the bowl. I'd also recommend a half a cup of meths in the tank too.

If it starts and runs OK at smaller throttle then the pilot jet is prolly OK so don't fark with that.

[Staticam]

I had another go at the bike today. Fired it up (very clattery), got it warm (still making a racket) and found that even while in neutral it will not pull high revs. I took the carb off. It’s clean and the diaphragm looks fine. I put it back together, restarted, same results.

This is where I’m at:
-Fuel and carb are clean.
-The spark plug I tried previously was used and the wrong temp but I figure has 95% ruled out a faulty plug issue.
-Clattery noise, sounds like valve clearance but could also be chain tensioner or something else?
-Wiring - the side cover has been off and on recently to sort out the starter clutch. It’s a real mangle getting the alternator wiring past the oil pipe.

It's such a waste just sitting there, what to do next?

I'm trying to sort it out without going to the shop, although I'll take on board any good recommendations.

[breakaway]

What is the state of the battery? How many volts does it show when you put a multimeter acrossit? Is there an in-line fuel filter? Have you checked the fuel line for blockages / kinks?

[Staticam]

What is the state of the battery? How many volts does it show when you put a multimeter acrossit? Is there an in-line fuel filter? Have you checked the fuel line for blockages / kinks?

Thanks for the ideas. The battery is one year old and has been on a tender which says it is ok. No in-line filter, lines are smooth, carb filled and engine started on first crank after having had it all appart.

[BoristheBiter]

I had another go at the bike today. Fired it up (very clattery), got it warm (still making a racket) and found that even while in neutral it will not pull high revs. I took the carb off. It’s clean and the diaphragm looks fine. I put it back together, restarted, same results.

This is where I’m at:
-Fuel and carb are clean.
-The spark plug I tried previously was used and the wrong temp but I figure has 95% ruled out a faulty plug issue.
-Clattery noise, sounds like valve clearance but could also be chain tensioner or something else?
-Wiring - the side cover has been off and on recently to sort out the starter clutch. It’s a real mangle getting the alternator wiring past the oil pipe.

It's such a waste just sitting there, what to do next?

I'm trying to sort it out without going to the shop, although I'll take on board any good recommendations.

I know this is a silly question but when you cleaned the carb did you clean out all the jets?
Had the same thing on my bike (it had sat for awhile) the main jet was nearly blocked. as soon as i cleaned it out it ran fine.