Zane 750 Engine Mods

If cranks are going to be made use the same cam chain size as the triples, a single row 3/8.

Its an 06B-1 chain and sprockets and platewheels are available worldwide very cheaply.

Also the chain will always be available.
 
Laverdalothar said:
don't you need to harden the pins again? Just wondering..  ::)
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I had pins on 3 cranks polished. Does not reduce the pin diameter. My guess is that if the bike is pulled down prior to self destruction the pins will be fine once polished.

I had one crank ground 10 thou under. Case hardening was sufficiently thick to take the grind without re hardening.

OS rollers are a necessity if using oem rods.

I had 4 cranks (8 pins) set up and checked for triangulation. No evidence. Also no evidence of micro ripples due to shonky grinding. All cranks, when measured, had consistently close to 55 micron clearance.(Loose, but not enough to cause failures.) I reckon the blame laid on the company that the cranks were outsourced to is wrong.

The KTM rods. about .4mm variance from the Zane rods. 750 rods shorter, 650 rods longer. What will be the impact on compression if oem pistons are used?

Regards, Greg


 
ghwallice said:
The KTM rods. about .4mm variance from the Zane rods. 750 rods shorter, 650 rods longer. What will be the impact on compression if oem pistons are used?
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Well, obviously a shorter rod will reduce CR and a longer one increase it. If you know the original CR you could work out the new CR from the change in combustion chamber volume.

A longer rod could be offset by using a thicker base gasket, as long as the cam chain will still go on.
Similarly, planning a bit off the head would compensate for a short rod.
 
Dellortoman said:
Well, obviously a shorter rod will reduce CR and a longer one increase it. If you know the original CR you could work out the new CR from the change in combustion chamber volume.

A longer rod could be offset by using a thicker base gasket, as long as the cam chain will still go on.
Similarly, planning a bit off the head would compensate for a short rod.
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Better to set squish height on the short rods by machining the barrel and retaining stock gaskets.
For the long rods, where I've done something similar before, I've made up metal base gaskets - usually aluminium.
Did a GSX400 Suzuki twin a while back with GSX750/4 oversize/taller pistons and made up a base gasket in 1.2mm alloy sheet. We're talking less than this for the Laverdas so there should be enough in the camchain tensioner to cope.

I take Andy's point about the chain. I'd assume from that, that the 8mm chain you suggested as an alternative is another scarce orphan size.
 
chrisk said:
Greg
I thought aluminium plate would have been better than sheet.
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It's all in the definitions, LOL. In the catalogues I have here, sheet goes up to 3.0mm thick and plate starts at 4.0mm...
I've usually got some 1200 grade half hard sheet laying around. More than adequate for the job.
Thickness seems to be held to good limits too.
 
chrisk said:
Reckon you could get a lot of work sorting out Aussie Zanes, given the duitch, and the exchange rate, you could have Zanes coming out your ears!
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I don't know if I want that...I'm within spitting distance of 70....The best info that I had was 6 zanes sold new here. Looks like there are more here counting immigrants. What sort of numbers are in Oz ?
What I can do is set up someone whose work I trust locally to carry on - if we can establish a viable regime to sort the cranks.
 
The iwis 8mm is a bit special and can be hard to get, especially when I stop.

The 06B chain as used in the triples will always be there.

Andy

Please note 06B is the DIN ref, used to order sprocket and platewheels
 
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