Primary Belt Drive.

Hello i've just bought myself a 1972 commando. I've never owned a british bike before. I was told that its been converted
from primary chain to belt drive. My question is do i run this dry of oil or do i drain it of oil and replace with new oil ????.

dry, and open up the clutch and dry that out as well.

Hi,
Elimination of primary case oil leaks and benefits of running dry clutch are two of the reasons for converting to belt drive in the first place.
Leave the oil out !

GB

Hi, I have had a belt primary for 12 years now.

Every couple hundred miles, I only go about maximum 50 miles per ride, I take the outer cover off and shoot brake cleaner all around in there and then wipe it all to to remove all the little
bits and powder of the belt that tend to fall off. Just me, but I think it important to do.

By the way, i just installed a new belt after all these years. The old one was still working fine, just thought it was time to do so anyway!

Enjoy your wonderful no lead dry primary!

But you still need to take the clutch plates out maybe once a year and clean them and the basket splines real good. Seems some gearbox oil migrates into that area and can gum things up.

Good job to do now for peace of mind with your new bike!

Just thought I should point out that there are belt drives for Nortons that run fine in wet primaries. The more common HTD style rubber belts run dry. Some of the polyurethane belts can run wet. With the dry belt conversions, you replace the clutch bearing with a sealed bearing, but with the poly belts, you can run with the stock ball bearing as long as you keep oil in the primary. Not sure why you'd want to run a wet primary with a belt, but it does get done occasionally. If you've got one of those, you just change the oil occasionally.

Ken

Thanks gents for the info. I'm complete novices when it comes to maintaining bikes. I've always had my serviceing done
by dealers. This is my first classic bike and the one i've always wanted. So its time to learn and get my hands dirty.

Northy, if you don't have already, you gotta get a clutch spring depressor to be able to flex the diaphram and then remove the big circlip and then you can take and clean your plates.

Much fun and quality garage time, takes little time do not fear anything!

Haha i'll try to show no fear. I carried out my first service on it with my head firmly in the haynes manual. And it seems to have been successful. Even in the cold mornings it starting on the second kick which brings a smile to my face. Had to replace the gear selector spring which was't a problem. Just can't wait for the warmer weather to come now.

Northy said:

Thanks gents for the info. I'm complete novices when it comes to maintaining bikes. I've always had my serviceing done
by dealers. This is my first classic bike and the one i've always wanted. So its time to learn and get my hands dirty.

Click to expand...

Trial by fire!

The most useful tool for Norton work is several boxes of nitrile gloves!

Northy;
Get a Factory manual, a Factory parts book,the INOA tech book and depending on where you live try to find a Norton support group to guide you. Join the INOA, this will help find other Norton owners in your area as well as some tech stuff. There is an amazing amount to know about these beasts and they can be very frustrating without some help, especially if you haven't worked on motorcycles before.

Scooter

lcrken said:

Just thought I should point out that there are belt drives for Nortons that run fine in wet primaries. The more common HTD style rubber belts run dry. Some of the polyurethane belts can run wet. With the dry belt conversions, you replace the clutch bearing with a sealed bearing, but with the poly belts, you can run with the stock ball bearing as long as you keep oil in the primary. Not sure why you'd want to run a wet primary with a belt, but it does get done occasionally. If you've got one of those, you just change the oil occasionally.

Ken

Click to expand...

Hidden in this bit of info is a really big tip. If in doubt you should pull the clutch basket and see what kind of bearing it has. You might discover you have a clutch rod seal kit as well. I assume you don't have any info on who made your belt drive and there are no identifying markings on the pieces? You can always post pics here as it is amazing the details some people here can pull out of a photo.

You can also download a factory manual in the tech section of this site. It is nice to compare it to the Haynes manual. There are a few spots where reading one and then the other can really help clarify the process. The blow up diagrams of parts groups at Old Britts have saved me a lot of grief in comparing different years and making sure the bits on my bike are standard (or not).

congrats on your purchase.