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About feetupfun

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  • Bike
    1963 to 1981

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    Gladstone Australia
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  1. feetupfun

    smokey mar

    Sorry it's synthetic mineral fibre
  2. feetupfun

    smokey mar

    Some Spanish bikes in the 1970s used wire wool as I discovered when I repacked my Cota 348 exhaust. The original arrangement was well designed with virtually no chance of causing problems. Yes I used some SMF to replace it
  3. feetupfun

    159 engine rebuild

    As for the size of the rebore, get the cylinder measured up by the person who is going to do the rebore and they will be able to tell you the smallest oversize that will work
  4. feetupfun

    smokey mar

    Why are you glad you didn't burn it out?
  5. feetupfun

    smokey mar

    If you've still got smoke coming out the exhaust after you stop the motor, it means that combustion is happening inside the exhaust pipe which means that there is gunk in there. If you want to be smoke-free sooner rather than later, then take the pipe off and clean it out. A transmission oil leak into the engine produces foul-smelling white exhaust smoke and if that was your problem the spark plug tip would look oily and your primary drive case would be losing oil fast.
  6. feetupfun

    Petrol tanks

    The bubbles that form when people paint these tanks are also an indicator of something permeating through the plastic
  7. feetupfun

    The First Chinese Trials Bike

    I suspect that oni nou's post was intended to be interpreted as being sarcastic humour
  8. feetupfun

    Cota 349 Gear box selector drum

    bigshineybike reminded me to mention that the 349 and many other spanish bikes of the time use 0.5 mm thick centre gasket, which is not a standard size here, but is available. The thickness of the centre gasket is important for things like the side play in the shift drum
  9. feetupfun

    Further storage questions from the novice!

    A friend of mine did have an arrangement with a bikers cafe where he would display his old trials bikes in rotation in suitably benign conditions.
  10. feetupfun

    Cota 247 Primary Drive Gear Puller?

    This is what I made to remove Cota 348 primary drive pinions. It worked a treat. The 247 drive gear is very similar to the 348.
  11. feetupfun

    No Snap!

    As long as the mixture is right there is no harm from poor combustion happening by having the air screw all the way in. However, if the pilot circuit is working normally and the air screw has to be all the way in to get the mixture right, then there has to be unfiltered air going into your engine somewhere which will cause damage. Have you checked the oil injection port for air leakage? On one of my bikes I had used a piece of plastic tubing to seal off the oil port and the tubing had swollen over time and had started to let air in. When you look at the LH crank seal, the evidence for a leaking seal may be very small. Even if there is no oil witness there, it can still be leaking. Sometimes that crank seal will seal in one direction but not the other, so air can go in but no fuel/air mix comes out, so no witness. I've just found exactly that failure mode on my KT250 LH flywheel side crank seal. One difference between a problem with the pilot circuit and a problem with air ingress is often that with air ingress via a crank seal or the centre joint of the casings, the degree of the problem will be quite variable, but if it is the pilot circuit that is the problem then the symptoms will be fairly consistent.
  12. feetupfun

    Seat / Tank unit

    I'm thinking that because bsw posted in the Yamaha forum, maybe the Miller tank/seat unit is from a Yamaha in which case yes one of the Shedworks fibreglass tanks would be a suitable way to go.
  13. feetupfun

    ty175 carbie

    I usually just tell the person behind the counter what it's for and they sell me an o ring made of the right stuff
  14. feetupfun

    TY250A piston to wall clearance?

    Wiseco pistons have a higher coefficient of thermal expansion than Wossner pistons, so need more piston/bore clearance (when measured at room temperature) than a Wossner. In theory the clearance is the same once the Wiseco is up to operating temperature. Running in a rebore is getting the bore and rings to bed in against each other so the contact surfaces can form a low-friction gas seal. While the running-in is happening, there is a lot of extra heat being generated by the friction of the rings against the fresh bore which can (amongst other things) cause the piston to get hotter than it should, which can cause the piston to get too big which can cause it to nip up.
  15. feetupfun

    ty175 carbie

    Could be, but not enough info to know for sure. How quickly is the throttle being opened? What happens when you try it with the starting circuit in service? It is doing the same thing hot and cold?