Author Topic: New guy from Canada  (Read 19409 times)

Jake2345

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Re: New guy from Canada
« Reply #25 on: July 06, 2014, 02:31:06 am »
Already had a mechanic look at the bike, engine is turning but absolutely no compression. He and a parts guy who has been around the block with different bikes both agreed that it was a blown push rod.

J6G1Z

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Re: New guy from Canada
« Reply #26 on: July 06, 2014, 12:00:32 pm »
Already had a mechanic look at the bike, engine is turning but absolutely no compression. He and a parts guy who has been around the block with different bikes both agreed that it was a blown push rod.

OK. Hang on a minute here. Push-Rods do not blow up. If anything, they bend, or the ends wear out. Non of this really matters though, as there are ZERO Push-Rods in your Ascot engine. You either mis-understood or you NEED a new mechaninc.

Was a compression test performed & if so, what was the compression pressure?

If it was not performed, you should still try it. If you know how to run a compression test properly, you can tell if you have bad rings, or a valve that isn't closing all the way. A re-ring is not the end of the world. Just depends upon the condition of the cylinder walls & whether you can get away with a dingle-ball hone, or it needs bored & the next larger sized piston. If the valves are not operating correctly, you won't be able to create a seal in the combustion chamber & build compression. This can be caused by several things. Bad valve seat, bent valve, erroded valve, broken or slipped timing chain, flat camshaft, etc.

When you run the compression test, you hook up your test gauge to the sparkplug hole, hold the throttle wide open & then crank the starter for a few seconds to rotate the engine a few times. Record your readings. Now remove the test gauge & add about a spoon full of 30wt. oil into the sparkplug hole. Re-install the gauge & repeat the test. Record your readings. If your first test was low compression & then the addition of the oil improved the compression number, you most likely have a poor ring seal. If there is no change between the 2 tests, then your valves are not closing tightly & sealing the combustion chamber. This will give you a direction to pursue.

There is also the thought of how much money you have in this bike & how much you like it before you dump more money into it. If the bike was beat to death by the P/O, you might be better off parting out the bike & then buying a cleaner example of a bike. If you are happy with the Ascot & want to keep it, now might be a good time to rebuild with some performance modifications made to enhance the fun level. It all comes down to how much money you want to spend.

Good luck
J.

PS. If anyone else has anything more to add, please jump in.

Jake2345

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Re: New guy from Canada
« Reply #27 on: July 06, 2014, 06:26:29 pm »
I may have the name wrong but I have ZERO compression, the piston is not moving

J6G1Z

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Re: New guy from Canada
« Reply #28 on: July 06, 2014, 08:19:21 pm »
I may have the name wrong but I have ZERO compression, the piston is not moving

How do you know that the piston is not moving?

If that is the case, then you most likely have a broken Connecting Rod.

That's not good, as it is usually very destructive. You will have to tear the engine down to survey the damage. What do you think you are going to do with the bike now?

J.

scottly

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Re: New guy from Canada
« Reply #29 on: July 06, 2014, 08:57:18 pm »
Did the motor actually go bang? A broken connecting rod usually makes lots of noise, and often punches holes in the crank case, but I've never heard of it happening on an FT, or XL or XR before.  :(