Airhead

youve sprung this on us Grouch,,,what are you doing then?

Ive seen it too john but only twice not had any issues with it...but when I browse not signed in I get a banner about a script slowing up my pc, have to click on 'stop running the script' , the banner you are referring to has a picture of two pretty girls

Great news Jimmy just in time for winter and all that salt

not to be sniffed at eh sniff :

You sure about them bein 6mm MRR slice? I would have thought 8mm myself

Hey bippo I assume you are continuing with the mammoth commute, keep on top of your chain lube and adjustment keep it regularly lubed, all this rain and the long distances you are covering will wash off the lube in days ........apologies if i'm telling you how to suck eggs lol

Great

Andy I always though that they had the valve and pulley fitted and simply pegged the U slot in the pulley through to the blind 4mm hole in the cyl head, therefore wide open...not talking through experience though...just what I imagined would be the method

It sounds like the power valve is 'Pinned open' Perhaps you will see some evidence of this if you look at the pulley attached to it. If it is 'Pinned' fully open then performance will be poor until a certain point in the rev band and when it hits that it will go like stink, could it be this you are experiencing. Having a working powevalve will help this situation because it will pull better with lower revs The 'power valve' is a mechanical rotating device that will alter the position of the top of the exhaust port for best performance throughout the rev range The 'power band' is the rush of power some 2 strokes exibit when they hit a certain rev range

Greetings Gareth and 1: Try it briefly without the air filter fitted 2:This doesnt make sense "in 1st and 2nd gear the power valve will kick in around 8K RPM, (2nd splutters unless i let off the throttle a tad) 3rd 4th 5th and 6th all have now low end power ( expected) but wont reach 8k rpm, and wont take off, top speed reached is about 50mph on a flat, it has no yvps control servo, and i have no idea what the problem could be, i took the carb off and cleaned, all seemed fine," I assume the power valve will never kick in because it's not functional...you mean it will take off in 1st and 2nd (Hit a power band) ?

does it have a carb? if so try draining the float bowl

Hi!

Greetings egghead and

wow thats a great job Pat whats the plan then...to keep or sell on for another project?

Thats a new one on me, the thundercat it a great looking bike, did you get a good un then?

Yes fit a new cleaner, it will just muddy the waters, you will lose vacuum if its holed and that will affect fueling meanwhile, loosen the petcck bowl just slightly, then drain the tank and remove the petcock completely take care not to lose or break the fiber sealing washer, you may find a filter gauze on the part that goes inside the tank...clean if necessary I cannot remember if the petcock holding nut undoes clockwise or anti-clockwise so with care try each way but dont over force it now remove the bowl you loosened and you will see another gauze held in place by the bowl sealing O ring, carefully remove that one and clean if necessary Tip*** do NOT try undoing the bowl using a 12 point socket or open ended spanner, the hexagon is soft material and will round off easily...use a 6 point socket

What are you saying here? Under power? Engine off and turning by hand? Just what?

Ahh so it is a project then What supports the weight of the rear light assy John, is there a steel under guard or something like the DT has?

Thats a different petcock to my Europan one then, does the bowl on the petck have a hexagon or square projection at the bottom? Fuel starvation will also be caused if your airfilter isnt sound (with no holes) and well oiled...this is a priority too

Heck John, It's not a project! Looks great, tell us more

Forget the carb for now if It's new Describe the rate the fuel flows from the disconnected carb feed pipe, It's hard for us to 'guess' what you saw

Yeah thats what I meant, now it looks like its worth investigating other things first although we cant discount the seals on such an old bike! Having read what you just posted, Perhaps there is and issue with carburation or fuel supply Take off the fuel line from the carb and open the petcock, you should have a good strong flow of fuel...have you? Have you stripped and examined the carburettor?

Inside the front brake plate you will see the speedo drive gear has two 'arms' on it, they stick out from the centre in opposite directions 180 degrees. These arms are often bent backwards because the people who assemble the brake plate dont see that the two arms must be aligned with the slots in the wheel hub when the brake plate is re fitted, check it out...bend them back...and re-assemble carefully if any of this applies While you have the brake plate off make sure the helical cable drive gear is turning as you rotate said structure with 'arms'

Before you dive in any further lets look for evidence that may go someway to proving the crank seals have gone bad. You say you have an issue with the engine revs climbing dramatically even with the throttle closed? This behaviour would suggest the left hand seal is passing air to the crankcase...so theres a simple test to confirm this start the engine and with the straw attached to the aerosol spray some WD40 through the slots in the flywheel, take aim at where the crank seal will be in the centre. It this seal is faulty you will see the engine revs drop back down, you will certainly see or hear a change in the engine behaviour, give it a try

yeah good puma, maybe just go for little rides at dusk rather than darkness until you have confidence