Top dead centre tool

[Threewheelbonnie]

I'm sure many people have seen this before, but as I had to make the tool to do the Guzzi's valves I thought I'd document it:



Andy

[MT350]

Looks very nice.

However, I usually use a cut down graphite pencil, seems to work just as well...

[backofbeyond]

I've got loads of those posh "R" plugs lying around in the garage. Given that they were the root cause of a misfire on my ancient Honda I might just do stage one of your instructions and leave it at that.

[Warin]

I have a dial gauge for that ... the timing on a Montesa required it.

On tour .. a stick will do.

I recently purchased a second dial gauge .. for truing spoked wheels.. so much easier when you can see and put a number on what is going on.

[backofbeyond]

Originally Posted by Warin

I have a dial gauge for that ... the timing on a Montesa required it.

On tour .. a stick will do.

I recently purchased a second dial gauge .. for truing spoked wheels.. so much easier when you can see and put a number on what is going on.

Yup, if you're into hair trigger timing ancient two strokes you'll need a dial gauge. I've gone through a few pistons over the years with RD's et al when the setting has been less than optimal.

I probably spend more time messing around with the dial gauge on my old H1 Kawasaki triple than I do riding it. It's always annoyed me that on something where thousandths of an inch matter the adjustment method is based on tapping overlapping base plates round with a hammer.

[Threewheelbonnie]

I always do my MZ's with a thingy like this one. It is more advanced as half the diameter of the rod and threaded bit is milled off at different heights*. The resulting steps were then filed for hours, measuring with a feeler, so when the piston is the right distance below TDC the step is just going flush the threaded bit while at TDC its by the higher bit. The trick is feeling for TDC then screwing the thingy up or down onto the top mark.

*This was made when UK engineering firms had actual machine tools that could be piloted by mortals and anyone else doing "Friday" jobs.


Andy

[oldbmw]

Originally Posted by Threewheelbonnie

I always do my MZ's with a thingy like this one. It is more advanced as half the diameter of the rod and threaded bit is milled off at different heights*. The resulting steps were then filed for hours, measuring with a feeler, so when the piston is the right distance below TDC the step is just going flush the threaded bit while at TDC its by the higher bit. The trick is feeling for TDC then screwing the thingy up or down onto the top mark.

*This was made when UK engineering firms had actual machine tools that could be piloted by mortals and anyone else doing "Friday" jobs.


Andy

Things like this... My Holbrook being re-comissioned in the barn