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Wont fire after rebuild


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Before I tore it down it ran great considering that the left side was only at 90psi. Here is a list of what I did:

Bored .020 over

Weisco Forged piston kit

Had the head shaved .040

installed and adjustable timing plate (set it at +4 degrees)

installed the motion pro TORS removal kit

took off the twist throttle and put on a stock thumb throttle.

K&N air filter

 

I filled it with fluids yesterday and tried to fire it up. On the third kick it popped once and that was it. After that it nothing. I was thinking that it might have something t d with removing the tors. I unplugged the tors box and both plugs that went into the old carb tops. The thumb throttle throttle has a wire on it that isnt plugged into anything. When I got the bike it had a twist throttle (with the tors) on it, so there was no wire attached to the throttle. Just a 2 prong lead that has electrical tape on it, but it has a different plug than what is on the thumb throttle that I bought used.

 

ideas of where to start?

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Yeah. Just use a business card. I think its .018 for the gap but I might be wrong. Its been awhile since I did mine.

Thanks for the help so far! I checked the gap it was a little more than a business card (not much). I adjusted it in, but I still have the same issue. I pulled the flywheel to make sure that the keyway didn't sheer off. That all looked fine.

 

I did get another pop through the exhaust (very little). I can try to spray some starting fluid in the carbs to see if it will fire off. Although I would prefer not tp do that unless I had to.

 

Question: SInce the top end has just been installed. Should I be able to turn the flywheel by hand? Because I can......

 

Any other thoughts?

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with the plugs in, it shouldn't be easy to turn with the flywheel by hand. you should have to put an effort into it.

It takes some effort, but not a whole lot. I was just wondering if the shop that did the boring screwed up. Can you do a compression test before you break in the top end to check it?

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Did you unplug the tors box? Did you do a compression test? When you pull the plugs are they sparking and are they wet with fuel?

Yes I unplugged the tors box. No I didn't do a compression test. I'll do that tonight when I get home. I had the head shaved down .040 when I did the rebuild. The machine shop that shaved it told be that I sould be somewhere about 165 psi. Does that sound about right?

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What are your mods, and what jets do you have? You could be lean on your pilots.

20 over, forged pistons, Toomey T6 Exhaust, K&N Filter (no lid), Shaved Head .040,

 

Jetting is set at:

280 main

Pilot #25

4th clip on needle

1.5 turns out on air screw

 

Keep in mind the bike ran great and always started by the third kick before I tore it down.

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20 over, forged pistons, Toomey T6 Exhaust, K&N Filter (no lid), Shaved Head .040,

 

Jetting is set at:

280 main

Pilot #25

4th clip on needle

1.5 turns out on air screw

 

Keep in mind the bike ran great and always started by the third kick before I tore it down.

Is there something special that you need to do when checking the compression? Because last night I screwed in my compression tester, after 1 kick it was at 65psi, 2nd kick 75, after 5 kicks it was at 95psi. This top end has never be fired up. So either I'm doing something wrong (which I'm hoping I did) or the machine shop that bored the cylinders messed up.

 

Any ideas or thoughts?

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Are you holding the throttle wide open as you kick? Are you using a long enough attachment to screw into the spark plug hole (the thread should be as long as your spark plug threads)? What kind of tester are you using?

Also, just keep kicking until the needle stops moving.

Was not holding the throttle wide open. the attachment is the same as the plug. Cant remember the name, but I just picked it up at the local auto parts store

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