1973 250 Clutch Plate specs ? Sprockets & now shift shaft !!!!

[Husabergpete]

Gents,

Does anyone know the tolerance or wear limits on what appear to be original plates. There are not steps our gouges on anything. I have looked through the Clymer book but no spec.

also what are the best replacements for them if I need to go that way.

Ta

Pete and Carl

[tony27]

Steels or bronze?

The later clutches like you should have run 3 steel plates measuring 1mm, sidepipe & maybe slightly later run 2 that measure 1.5mm

Don't have my vernier at home to measure the new set of narrow bronze plates that I have but will do tomorrow unless somebody else does beforehand

Genuine bronze plates aren't hard to get, should be able to get them from VMXunlimited,CRHighperformance,CZstuff or Lee Holth

[VMX60]

Pete

Run Barnett plates wet or dry  much smoother feel and they dont drag when hot as the CZ bronze std plate

Barnett from Serco Qld or Les

Cheers

[Canam370]

Been using Barnett plates too. Very good. They aren't affected by the inevitable leaky seal in the clutch either.

[Husabergpete]

Gents thanks so much. We get so much from this forum. Brilliant. I will chase Les.

All the best

Pete

[tony27]

Doesn't swapping to the barnett plates involve springs & steel plates as well due to a difference in thickness & possibly number?
Haven't had any experience of this myself as I'm still running the standard stuff but the wet clutch kit that CR sells seems to have all these parts & I've read something about using different springs in the wet clutch
http://crhighperformance.com/?wpshop_product=cz-wet-clutch-kit-104-95

[Husabergpete]

Tony, thanks for the info. Will measure up plates etc but they seem ok.  What sprocket ratios would you recommend??  Currently we have 14t and 53t  and intend running it in the Heaven MX events such as Canowindra grass track.

All the best

Pete

[VMX60]

Pete

Only ever used the Barnett fibre plate kit with all std CZ other parts worked fine over 8 years then replaced the steels all good again

Plus you can run wet or dry setup

Last few years the complete wet kit has appeared from CR  told their thinner plates and lighter spring combo unsure of the details

Cheers

[shortshifter]

I think standard was 13 and 52 teeth so 14 and 53 should work out the same???

[shortshifter]

I have been reminded by a mate that going up one 1 tooth on the front = 4 teeth on the back so  if you wanted a 14 at the front you would need a 48 at the back to keep it the same as 13 and 52.Cheers Simmo

[Bamford#69]

Hi,
yes, everyone noticed your deliberate mistake ;

if you want to keep the same gearing ? as 13 front and 52 rear ( 4.000)
with  14 teeth on the front  you will need 56 teeth on the rear,
(14 front and 48 rear will give you 3.428)
cheers

[shortshifter]

As you can tell,the mathematics of gear ratios are definately one of my weak points .Cheers for clearing that one up Mike

[Husabergpete]

I am no maths guru either.  Just czecking I get this kinda right I should run 13 - 52t or I spose a 53 wouldn't change things that much.

Next thing is we now need the gear shift selection shaft. Ours slightly bent and twisted. - Bugga

Pete and Carl

[tony27]

52T is standard rear for 250 & 380 or 62 for the 125, really depends how tight your tracks are as to which front you use but either 13 or 14 should be fine

Gerard Copping at www.czstuff.com lists the shafts for 24.50GBP, not sure if they are a complete assembly or just the actual shaft which you need to weld to your original mechanism. The guy in Poland lists both types on ebay sometimes & on their site 

[shortshifter]

If you are getting a shaft with a mechanism welded on make sure it is the right one: 4 and 5 speed are visually very similar but not interchangeable,the wavy things on top are different.No way of straighening the shaft??Save a bit of mucking around.