Primary chain

Hi All

Has anyone run a triplex primary chain on a open primary case, wondering if just spraying the chain with chain lub will be enought to keep it lubed, the reason why is I want to go back to running a chain as I have had a few issues with my belt drive, my inner case was damaged many years ago from a thrown chain, I have cut the back out of the case where the clutch basket is and front of the inner case has 2 vents cut into it, I want to keep running the dry clutch, I can spray chain lub on the chain while the motor is running, I still run the full outer case.

Any throughts on this would be helpfull, I am going to give it a go but if it don't work I have a spare inner case, I have been using Inox chain lub on my rear chains on all my bikes for sometime now, when sprayed on it sticks like glue and don't fling everywhere, I usaualy get over a months ridding befroe it needs spraying again (1,000/1,500 kys).

Ashley

Ashley, I do not have direct experience with your proposed experiment.

However, I don't see why not give it a go as your quality chain wax is likely just as good a lube as ATF or regular motor being sloshed or misted onto in a sealed primary.

You can keep a close eye on things and keep spraying the sprockets and chain while idling anyway.

I wouldn't be riding on any dirt roads that way.

Not to many dirt roads around where I ride these days and if I did I be on my dirt bike

Plus I am not ridding my Norton as much now since owning my new Thruxton.

Ashley

You're lucky.

I use a single row primary chain on my 850, and I spray it with chain lube before a meeting. It lasts without problems for at least four four lap races over a 3 Km circuit which has two long straights. I always wire the joining link.

That open inner primary behind clutch basket exposed to sprocket chain dirt-roady gunk and grits has to be a compelling reason to install a new one.

I have put the triplex chain back on and will be taking it for a run today some time, before I put the outer cover back on I will start it up and give the chain a good lub, I will then go for a good ride and keep a eye on the chain as I can see it fron the top to the bottom of the clutch housing, if the lub last every ride I will keep it this way, only time will tell, not a big job putting the other inner case on.

Ashley

I have been running it like this for a few years now and you be surprised that not much dirt or road grime gets into it at all, the only problem I have been having with the belt drive is it wants to keep running off the front pully, all the belt teeth were still good but it worn my belt 4 mm on the front side of the belt, it has only done this since I put the alloy belt kit on, the steel kit I didn't have any problems with, I run double adjusters and the pullies were lined up right, I would have put the steel belt drive back on but I haven't got a spare belt.

When I pulled the clutch housing off it was still clean behind it no grit on the shartf and the sealed bearing was still clean and running smooth, I am still running my standard clutch plates (bronze and steel) they have been on the Norton since new and have done just on 140,000 miles and have just replaced the clutch centre a few months ago for the first time, my orginal clutch housing and front pully are still in very good condition with no wear at all, but this will be the third triplex chain in a 120,000 miles.

I don't have any problems with gear box oil getting into me clutch as I don't over fill my gear box, (I messure my gear box oil and only put in the reconmended amout in) I put grease on my clutch rod and have been doing this for 37 years now and I have never had any gear box oil on my clutch plates, but do get oil from the primary oil bath, since running a dry clutch I have had no problems with slipping or dragging clutch and thats the reason I want to keep it like that, these clutchs work so well without oil on them.

Ashley

It is not a good idea to run any chain in an open case.

Speedway guys do and even though they throw lots of lube at it, going out and
coming in after each race, they still have problems.

Many racers with 1/2" primary chains now run O ring chain which seems to work
very well.

It is not the road dirt that ruins the chain it is lack of lubrication. A Commando primary
has 93 bearings, pins/bushes, and they need lube. Run your wheel bearings dry and see
how long they last.

Andy

I tried running a Commando triplex primary chain using only chain lube at a race at Laguna Seca years ago, and it didn't even make it through a practice session before it broke. I never tried it again. I only tried it that time because a crash had damaged the outer primary cover so that it wouldn't hold oil, and there was no time to repair it before the race. It didn't end well. When the chain broke it took out the alternator and inner primary cover as well.

I've also had some limited experience with running a conventional single row chain on a friend's Norton race bike with an open primary. Lubing the chain before every practice and race sort of worked, but the chain didn't last very long, and wore so rapidly that it jumped the sprocket and caused at least one DNF. He eventually replaced it with an 0-ring chain, and that seemed to solve the problem. Still, when the Atlas style clutch disintegrated again, he finally gave in a went with a modern belt drive primary. A total loss drip oiler, as used in the bad old days on race bikes, would probably have worked fine, but none of the racing organizations allow that now.

You may have different results on your street bike, but I doubt it. Like Andy said, the triplex really needs to run in an oil bath for longevity.

Another concern you might have is the loss of lube for the clutch bearing, unless you have changed it to a sealed bearing, as used in the belt drive primaries.

Ken

Thanks for confirming my views.

The 1/2" O ring certainly works on "older" race machines but I would have reservations reagrding
a Commando.

I do not like triplex chains as there is an in-built flaw. Too long winded for here. This flaw is cured
by using a Merc Diesel chain and I stress diesel as it is very special. Again too long winded for here.

Just for clarity my name is Andy and I am The Chain Man (google it). I supply many classic bike chains
including increasing Commandos and have been made aware of several problems re chains. My aim on
the forum is to educate and help not sell. To that end Sprockets Unlimited (Jane) sell the same product
as me, and no we are not "mates".

It would be nice to see any of you at shows, next one tomorrow at Founders Day, then Kempton and
Ardingley.

Andy

Thank goodness the ancient triplex chain flaws can endure for 10's 1000 miles, but i've seen mine loose the link roller barrels. There was a discussion a decade ago on Brit Iron and NOC list about racers having siezed 1' chains tll they lowered oil grade to 20. My Peel project may need to go back to triplex chain gang if the Maney 40mm HTD belt can't take the torque hits over 100 lb ft so may need to buy some your diesel grade chain. I expect tire traction will act to protect the primary drive though.

Well I went for a ride the other day with just chain lub on the primary chain, I did about 40 miles then when I got home I pulled the outer case off to see how the chain was, all good so far the chain and sprokets still had lub on them and the chain wasn't hot at all, I will take it out this weekend and will do about 200 miles and will see how it goes, I will be taking the chain lub with me and will keep a good eye on it.

Ashley