Bushing Commando small ends

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Does any one have experience of bushing commando small ends? Can I buy bushes to press in once machined out?

Thanks

Nigel
 
I have not tried putting a bushing in a Norton rod. I would be afraid the reduction in wall thickness would weaken the small end.

I have honed the rod and piston for the next size metric wristpin very successfully. In fact that is what has been in my streetbike for about 15 years. Jim
 
Do you have a website Jim or is there a list somewhere with services available.
Les
 
Time Warp said:
Do you have a website Jim or is there a list somewhere with services available.
Les

I have never finished a web site. I'm just a one man operation and usually stay pretty busy.

I can do just about anything you would need done to a Norton engine other than crank grinding or balancing. Jim
 
Torontonian said:
The Commando small end does not wear out. There are bigger issues to put your energys into.

Well might not wear out but there is definately a little too much play. The PO had a non return valve fitted and probably starved the engine of oil once or twice nackering the bigends and possibly seized the rist pin at some time.

Anyway the honing sounds like a good option just nee to see where I can source the oversize pins.

Thanks
 
Adding up the tales I've read over about 15 yrs my Norton learning curve on 'wet sump stifle devices' sure has cost collective owners way more than the rare crank seal leak issue and likely a bunch of cam lobes too. What about plating the pin, chrome or nitride then micropolished to fit the cleaned up piston bore? There might be an issue with the pin retaining clip if too much piston bore removed but have heard success with the teflon retaining pads if still trying to salvage used parts.
 
hobot said:
Adding up the tales I've read over about 15 yrs my Norton learning curve on 'wet sump stifle devices' sure has cost collective owners way more than the rare crank seal leak issue and likely a bunch of cam lobes too. What about plating the pin, chrome or nitride then micropolished to fit the cleaned up piston bore? There might be an issue with the pin retaining clip if too much piston bore removed but have heard success with the teflon retaining pads if still trying to salvage used parts.

Sounds like a great idea! There is not much play, so the plating might do the trick :-) Pistons are new with wrist pins. I'll have a chat with the guy at the engineering shop to see what he can do - did a cracking job on my cylinder head and re-bore of the barrels absolutely spot on - 4 thou clearance after honing.

PS I will never ever buy another bike that has had a non return valve fitted either spring loaded or on/off type valve - the worst idea that anyone on this planet ever had!
 
So what's wrong with an on/off type valve? I've had one on my 850 for several years without any problems, I do have ignition interlock on it so no chance of starting with the oil switched off!

Dave.
 
comnoz said:
I have not tried putting a bushing in a Norton rod. I would be afraid the reduction in wall thickness would weaken the small end.

I have honed the rod and piston for the next size metric wristpin very successfully. In fact that is what has been in my streetbike for about 15 years. Jim

+1
 
Oh my Nigeldtr this wet sump worry and devices are sure costly compared to what they are supposed to help. Norton rods are over built to point they have no fatigue cycle limit in under 100 hp engines below 8000 as long as they still have enough small end meat. I assume not much mass difference with a new over size pin to match to un-machined side?
 
Why not just purchase new or used replacement connecting rods? The cost savings spread for an oversized wrist pin may not be there unless you have the means to do all the work yourself. You will be faced with the sourcing, purchasing and shipping of oversized wrist pins, take/ship pistons, OS wrist pins and rods to reputable machine shop to ream to fit, and then ship/pick up finished product.
 
Dances with Shrapnel said:
Why not just purchase new or used replacement connecting rods? The cost savings spread for an oversized wrist pin may not be there unless you have the means to do all the work yourself. You will be faced with the sourcing, purchasing and shipping of oversized wrist pins, take/ship pistons, OS wrist pins and rods to reputable machine shop to ream to fit, and then ship/pick up finished product.

New rods are definitely easier.

One nice thing about the metric pins is a better selection. The metric pins are available in high strength alloys that are thinner walled and lighter and can be had with tapered bores. Jim
 
If yeah mess with one side's pin mass very much then better do similar to the other side, so double the ta$k. Simplest of course is sell off your core to CNW and take home a show room model or special order and just ride ride ride instead of wrench wrench wrench.
 
daveparry said:
So what's wrong with an on/off type valve? I've had one on my 850 for several years without any problems, I do have ignition interlock on it so no chance of starting with the oil switched off!

Dave.

Hi Dave,

Nothing at all. The problem is, a lot of people seem to fit the "suction" type or the on/off version. I am convinced the "suction" type don't open when the engine is hot and ticking over - low oil pressure and buff, there go the big ends. The on/off type, just as you are about to turn it on, the phone goes, forget you haven't opened it, off down the road and a few miles alter, totally knackered engine. I hate the mess of draining the sump, but seeing so many knackered engines caused by valves, is enough to make anyone cry.

PS the electrical cut out is a great idea BUT another point of electrical failure which can be jumped to test and then forgotten ! Anyway I prefer to fail safe (oil in sump) and not fail "bang". Sorry if I cause worries but seriously, it makes such a bloody mess when a valve, switch or memory fails!





Regards

Nigel
 
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