timing wheel (tool) use

Joined
Aug 26, 2005
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Hi all - where can I find some info on the web regarding the use of the T.J. Wassell timing tool?

Many Tks!!! You all make this a Great site!
 

ILLF8ED

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Dec 30, 2003
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TJ Wassell Engineering

If your talking about a timing wheel, what information are you looking for?" This is a protractor that attaches to the crankshaft end to indicate degrees of crankshaft rotation usually compared to top dead center of piston movement. Useful for ignition and camshaft timing.
 
Joined
Apr 7, 2004
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First you need something to stop the piston near the TDC. You can tap a spark plug and put a socket head cap screw in it. Brake off the ceramic part of the spark plug and remove the hook on that end and drill it out #29 drill,then tap the hole #8-32. Use an 8/32 with 1 1/4 of unthreaded shoulder. run it in till it bottoms out. than cut off the head of the bolt and grind a bullet shape on the end. If you go biger than 8/32 your valves will hit the tool turning in a lathe to 3/16 is the best.

Get the bike up on the centre stand and put her in high gear.Using the rear wheel bump the motor around and get the pistons down. Put your dead stop tool in and gently bring the piston up against it.
Put the degree wheel on the end of the crank You will need to adapt it to fit. Not tight just yet. Now bump the motor very slow and gentle to the stop.
Wrap a wire around a couple of jug nuts and make a pointer out of it at around 12 oclock
Set the dial on the wheel to an arbitrary number like 30 BTDC . Now bump the motor around the other way until it stops using the same gentle feel. In a perfect world it would come out to 30 degrees but it won't. Lets say you get 40 Now you may want to slip the dial a bit to try 5 Bump the motor back and you should get 30 the other side of TDC
You want to end up with the same number on either side of TDC then snug the wheel and re-check the number is not important just be the same each side.
Now remove your tool and you can move the motor around to TDC zero degrees using the pointer and the degree wheel You can now find 31% BTDC.
Set it at 31 then put your chaicase on and see how close your gauge is to true 31 degrees and how the cover can be moved around to make it read all over the place.
 
Joined
Dec 5, 2005
Messages
90
Can I ask a stupid question.

Is 31 degrees the correct BTDC setting or is it 28?

The little degree plate thingy has got chewed in my chain case, I have made up a new one and need to calibrate, so I am interested in the correct timing point.

Cheers Richard
 
Joined
Apr 7, 2004
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1,691
It's probley better to buy the degree wheel for the cam mount. Still use your dead stop and leave the primary cover alone. Each time you remove the cover it will end up in a little different spot. Because the cam turns at half speed the wheel is egg shaped these are on ebay all the time.
What I have found is that Commando's that have good carbs,battery,wiring,Boyer,good plugs and wires are very tolerent on timming. So once set so they stop advancing at the corrected 31 degrees and the adjustment screw on the boyer plate slots are in the middle, you could run it anywhere in the slot and not hear or feel much differance. There not like Triumphs or BSA's because of the combusion chamber. Just don't want you thiking your going to have a rocket because your close on the timming.
 
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