Terry Prince Top End Kit

[Bill Thomas]

Sound's FUN, I am just about to start Welding my 560 flywheels !.
Funny, Brother Ron came round the other day, He only has a Comet now, He finds a Twin too heavy to push around, He's OK once it's going on the road.
He said how powerfull the Twin was we built for a friend, We both road it to see if it was OK, Been in bits since the 60s, Bog Standard,
We only put together what was on the floor , With new tyres and a bit of paint.
I said if you think that was good, Don't ride my ex L/ning rep', He never has, And my Special is far too tall for him, So he never had a go on that either, It's a different world !!.
But I love my Comet in another way.
Will be interesting if I can feel any difference with another 60cc, As long as I don't cock it up !!, If I do it will be another 500 !!.
Good Luck with yours, Send lots of photos, Cheers Bill.

 

[bmetcalf]

I have not yet asked him what type of HD unit he pictures here. They seem to only be available in pairs and are pretty expensive. The CR threaded hole is 12mm, as are the plug holes:

These http://www.sputhe.com/automatic compression release.htm are $60 for a pair, if the site price list is correct. I didn't look to see if they are 12mm, though.

The Bay http://www.ebay.com/bhp/harley-compression-release has single units.

 

[Oldhaven]

I have heard not to use the ones with plastic heads, since they won't stand the heat up under the head bracket. I would also guess that the cable or electric operation types might be easier to use due to the centered location (not using a spare plug hole).

 

[davidd]

The compression release may take a little research. How the valve is designed, that is how much compression it releases and how quickly, takes a little bit of research and trial and error. Many have complained of bad starting Harleys due to too much compression being released too quickly.

If size is a problem, Alloy Art seems to have adapters available.

http://www.circlecycle.net/alloy-art-compression-release-adapter-detail.htm?productid=23101069

David

 

[vibrac]

It will be interesting to see if you have problems with that head Last year I watched some of tha antics necessary to sort one before it went on a big bore comet nothing wrong with the design thats great it was just some of the limits on holes and threads needed attention perhaps it was a friday 4 oclock one

 

[Oldhaven]

Word from Terry is that the decompressor is from HD twin cam:

Harley de-compressors genuine Harley twin cam solenoid 28861-07A

And it is available singly and is relatively inexpensive at around $40. Being a solenoid I imagine you just power it on before start. Suppopsedly it closes when the engine fires. I'll get one eventually and experiment to see if it is momentary or continuous power on. I really see no way to do a manual CR in that position between two plugs. I can just imagine trying to stick my finger in there after stalling at a light. He does supply a plug to close it if a CR is not used.

On the threads, I tried them all and aside from having to clean up the threads in the oil feed "blocks" a bit from the installation of the hose barbs, all is good.

 

[davidd]

The Harley solenoid works on the starter circuit, I believe. It also exhausts into the exhaust port rather than the atmosphere, which should not be an issue. Pat has been using the pop up decompressors on the Lightning. They work fine, but we have been starting it on rollers. Pat has a second plug hole in the Lightning heads, but it is single plug ignition.

David

 

[chankly bore]

On my build I needed to file out the very edge of the liner flange to allow the head studs through. The Hoggly Doggly solenoid is good, you should be able to engineer a breather ball valve at the original lifter entry point. At least it will be a bit more "sightly" than the verfluchte Elephant's Trunk.

 

[teunvandriel]

you should be able to engineer a breather ball valve at the original lifter entry point.

Do you have a picture or drawing please?

 

[Bill Thomas]

you should be able to engineer a breather ball valve at the original lifter entry point.

Do you have a picture or drawing please?

If you are looking for a new type of breather, I have seen a neat one on ebay, Fit's where the adjuster cap, Front inlet.
It's done by one of our Forum blokes.
I don't know if it works, But I would give it a go if I needed one.
U.K. ebay number 222463044698.
Cheers Bill.