Questions? Looking for parts? Parts for sale? or just for a chat,

The WD Motorcycle forum

WD Motorcycle forum
Start a New Topic 
Author
Comment
View Entire Thread
Re: Quality

You need to get a new clutch hub / spline /adapter / center / whatever you want to call it .
While they all seem to get the same part number the tapered hole is deeper on some than others so this changes the position of the entire clutch
Later models with an alloy chain case have smaller holes and sit out a good 1/4" to 1/2" on the main shaft
Centers for tin primaries have a bigger hole so sit further in.
Centers for pre war bikes that only had an outer cover sit further in again
I think it was here that some one went to the effort of photographing about 1/2 a dozen of them showing the different sizes .
I have had some ground out larger in the past ( not cheap ) but you can't turn them because they are both cased and have the keyway which eats up tooling .

email (option): bsansw1@tpg.com.au

Re: Quality

Trevor I have the correct "Les Harris" adapter for an M20 main shaft. But for some reason it's still out by 3mm. I guess the chain could cope with this, but I'd rather get it as near spot on as poss. The standard adapter (BSA part) that most dealers sell is the one for the smaller main shafts on the A & B boxes. I don't know if anyone else other than Harris make the M series adapter? Ron

email (option): ronpier@talk21.com

Re: Quality

The 4 spring M20 adapter I got from Kidderminster also had the clutch stick out too far by a small amount. This was because the adapter was stopping on the shoulder of the main shaft before the taper fully engaged. It felt OK putting it together until you noticed that the adapter could be removed by hand once the main shaft nut was off.

Tighten the main shaft nut and see if the taper locks solid. If not you have the same problem as me. About .020" needed to be removed from the adapter before the taper fit and the sprockets were in alignment.


Thinking I received the wrong part, a friend with Goldstars gave me a 4 spring B series adapter to compare and it was definitely different to what I have. With the B series adapter the clutch was too far out at least 1/4". But the taper did lock properly.

So I am thinking I have the correct part but not made correctly???

My M21 is running now with the 4 spring and has a clutch that actually works!

Bruce

Re: Quality

Bruce I did note your comments about this originally.

Even with my adapter just nipped up without the woodruff key, I still had to use a puller to remove it, and measuring the thread also confirmed that it's fully home. Obviously some variation in these parts :confused: Ron

email (option): ronpier@talk21.com

Nieuwe pagina 1