Chain oil

[rotarian]

Hi, I have filled my rear chain enclosure with the stated amount of oil, and gone for a short ride,when I returned I found oil all over the left hand side of the tyre and lots over the rear sprocket cover! I think it is leaking out of the chain gaiter, has anyone got any ideas on how to stop this? The cable ties around the gaiters are tight and the gaiters seem in good condition.

[Richard Negus]

Commiserations !Air-cooled or Commander ? You don't say which.If Commander, then sure to be the gaiter perished at the convolutions.If air-cooled, then it could be the big oil seal in the sprocket cover plate is leaking.If Graham at Startright hasn't got a new seal, then your only solution is to use less than the recommended amount of oil. The seal was a 'special' and not a catalogue item ; NML don't have any left.The manuals are a bit ambiguous about the oil quantity ; 125ml is the 'new' fill when the system is completely dry ; replacement amount is no more than 100ml as oil can be trapped in various places and never drain out.Drain the oil again and measure the quantity ; if there is much more than you expect, see if it smells like gearbox oil. If so, the gearbox sprocket oil seal has failed, allowing gearbox oil into the rear chain drive.When replacing the gaiter(s), a rivet link is highly recommended for security and rider safety.R.

[rotarian]

Thanks for that Richard,my bike is an air cooled,I will carry out the checks you recommend, but what is a rivet link?

[Richard Negus]

There are two types of connecting link for a rear chain.. a detachable link can be re-used and has a horseshoe-shaped spring clip to hold the removable side plate in position. Unfortunately, it can be wrongly fitted and come apart with loss of drive. On a conventional open rear chain, this isn't usually a problem ; the chain lays in the road like a dead snake and, sometimes, the crank case casting can be damaged. On the enclosed chain of a rotary, the chain usually wraps around the rear sprocket and locks the wheel. Bit exciting at the time - but there have been two serious accidents where the swing arm twisted and threw the rider off. One, a mechanic with the Met police, suffered (or claimed) serious back injuries and, I hear, never worked again. The rider of the other managed to retain control, I think.(Malcolm ??). a rivet link is a permanent connection formed in the same way as the normal links of the chain. It requires an assembly tool to press the side plate on to the pins and then to rivet over the ends of the pins so that the plate cannot come off again. Also used on race bikes for security reasons.After the Met police incident with an Interpol 2, Norton required all chains to be rivetted, even for the F1 and issued a Service Release ; an easy job with the right tools, and possible even without them.I always think and worry when riding someone elses rotary "has the chain been rivetted, or is today my unlucky day ?"R.

[Interpol2471]

Richard did the factory fit rivet links when doing repair work, for instance when my engine was rebuilt in 2002? Is there an easy way to tell or do you have to remove one of the gaitors?Thanks in advance.

[Richard Negus]

Richard did the factory fit rivet links when doing repair work, for instance when my engine was rebuilt in 2002? Is there an easy way to tell or do you have to remove one of the gaitors?Thanks in advance.

Paul,If only the engine was done, then the rear chain / gaiters were not necessarily disturbed.If the gaiters were replaced (because they were perished / leaking) then it was probably done by Tony Squire and he would almost certainly have fitted a rivet link.Two ways to check :-. detach the lower gaiter from the sprocket cover so you can see the chain.. remove the gearbox outer cover and oil pump mounting plate to reveal the chainBoth oily jobs - but I prefer the second as it's easier to get a good oil-tight seal there when re-assembling. However, if you find a split link, you've then got to detach the gaiter anyway to fit the rivet link.Beware that both Renold and DID chains were fitted at various times and the links are not interchangeable. NML number is 55-1428/REN or 55-1428/ES50, also available from elsewhere.R.

[Malc]

Richard,I remember the chain incident very well as it resulted temporarily of all IP2's in the country being grounded. The bike in question was a driving school bike D236 UNN and it had also been accident damaged a year earlier.Mid afternoon on July 31st 1989, got a phone call from the police instructor "we have a rider involved in a RTA, the swinging arm has collapsed".I was immediately dispatched from Derbyshire to Kings Lynn to recover the bike as for some reason they wanted the bike to stay at the scene until we recovered it. A telex message had gone out to all forces giving details and advising all bikes to be withdrawn from service until futher notice.Got back late evening, a message had been left to say that 2 bosses from NM ltd would be there in the morning, do not touch the bike.Next morning, you turned up with Bob Rowley and I had to strip the bike while watched by yourselves and our manager. All service records were out and I had a look and with some relief found that one of the car mechanics was the last to work on while I was on holiday.The chain had 'become unjointed' and wrapped against the sprocket carrier and the force had bent the swinging arm to the point of breaking.The chain had not snapped though, and the clip off the split link was found in the gaiter. Conclusion of all was that the clip had been put on the wrong way round. The lad who had replaced the chain gaiter a week or so earlier was asked what way round the split link should be fitted but would only admit to saying that he put it back the same way as it came off but could not state the correct way of fitment. It was standard practice to replace the split links once undone but I dont think this had been done either.The bike was loaded up later that day and I returned it back to Shenstone. I then had the bike back to repair the accident damage, as the rider had gone across the oncoming traffic nearly hitting a lorry before hitting the kerb and dropping it.There was talk of claims but I dont know the final outcome of that side of things.I then had to have all the other bikes back in to replace the split links with rivet links and from then on it was standard practice.The bike then had to have an engine build the next April at 20,412 miles, but dont have details of why. In my log book, I have down that it was again accident damaged in 1992 being de-commissioned as a write off 22/5/92 with 38,443 miles on it.Malc

[Richard Negus]

Hi Malc,Thanks for the reminder of that incident - your memory is much better than mine !I know many owners use split links and haven't had a problem - but, in my opinion,the consequence of a detached split link far outweighs the minor hassle of fitting a rivet link.R.

[rotarian]

Thanks Richard for the reply, I now of course know what you mean, I was thinking that there was a different way of fixing the gaitors as that was what you were talking about. I have checked my chain and it has the rivetted link. Are there any other safety points that we owners should know about, but are not readily known, except maybe by those that have come across problems, such as yourself?

[Richard Negus]

The chain link is THE safety issue with IP2, Classic and Commander. Other things are less significant :-. some IP2 wheels had cracks where the spokes meet the rim, but to the best of my knowledge, none have actually broken in service.. IP2 / Classic genuine Brembo semi-metallic brake pads corrode over time and the friction material separates from the backplate ; bear this in mind if you start to use a bike that has been stored for several years.. regular greasing of the IP2/Classic/Commander rear caliper plate bush will stop it seizing and perhaps breaking when you least want it to. Early IP2 plates had the grease nipple at the "9 o'clock" position (=break here!) ;later ones had more metal around the boss and the grease nipple at 7.30. . Commander rear wheels have a non-standard, un-sealed ball bearing hidden underneath the cush drive plate. When the grease dries up, the bearing fails and, if not spotted early enough, can scrap the wheel. Very expensive !. F1 steering head bearings tend to rust & indent the races ; rust because there's no ventilation and brinell because they are usually adjusted when the frame is cold. As the engine is run, the frame heats up and the head tube expands, overloading the bearings.. on all Norton rotaries, primary oil that comes out black, difficulties in selecting neutral, and a notchy gear change all suggest that the cush drive rubbers may need replacing.I'll have look through the old Service Releases and Problem Reportsand see what else appears - might be something worth publishing with EPI for a wider circulation than this forum.R.R.

[Interpol2471]

Richard has spoken He is the guru of all that Rotates

[rustynuts]

Thanks for this valuable advice Richard. I have just peeled back my chain gaiter to find a split link, fortunately fitted the correct way round. Needless to say the bike will not be going anywhere until a rivet link has been fitted.

[Interpol2471]

Richard what size chain is fitted as I am going to buy a chain tool and wanted to make sure it would do the job? Do the rivet links supplied from NML have the nipple indentation in the end of the split link pin?Thanks

[andygbsmith]

At Kempton some years ago I asked the Husband and Wife team that are "The Chain gang" what tool they used for riveting chains.It's a Japanese tool made by Whale. It's the simplest tool I have used and always does the job right.Expensive about £60 but you get what you pay for.Their one, was ten years old at that time and still doing a good job.Andy

[rustynuts]

I've just been overhauling my rear sprocket case (IP2) and have noticed something peculiar and wondered if anyone can help.The fixed spindle 44-0089 has a flanged end that sits against the sprocket hub bearing and within the oil seal 55-0826. The flange has an outer diameter of about 35mm, however the oil seal internal diameter is about 40mm = a big gap! What's going on? Is the seal too big? Is the flange too small? Is there some other part that is missing? From the diagram in the parts book, it doesn't look like I am missing anything. There are no marks on the flange to indicate it has ever made contact with an oil seal and the lip of the oil seal looks unworn. The sprocket hub bearing is the sealed type so is doing the job of retaining the oil, although a little is leaking past and escaping through the mystery gap.

[Richard Negus]

Hi,You have a non-matching set of bits !Although sealed bearings will keep assembly grease in the bearings, they don't resist a positive pressure too well and can leak - as you have noticed.The sprocket carrier and spindle were modified to add a conventional oil seal to stop the occasional leak. The carrier was bored out to suit a standard seal diameter and the spindle end increased, again to suit a standard diameter.You have an late type sprocket carrier with an early spindle.You should also have 3/8" UNF bolts to hold the sprocket ; early carriers had 8mm bolts and were known to break on occasion.I'll check correct part numbers and stock at NML later today.R.

[Richard Negus]

Hi again,I had a look at the parts catalogues and the NML stock & confirm that you have an early spindle 44-0012 with a later sprocket carrier 44-0094 ; the change happened in about 1985.If you wish to correct it, you can either buy the matching spindle 44-0089 or fit a sleeve to yours ; the seal is actually imperial size with a 1 1/2" bore ; a steel sleeve, fixed with Loctite 648 was used by Norton to convert 44-0012 to 44-0089.R.

[rustynuts]

Thanks Richard, I will contact Peter Morris tomorrow. I miss the days when I had access to machine tools at work and coud have turned a sleeve up.However, after just having spent an age extracting the wheel adjusters and a load of dried out grease and rust from the swinging arm, I never want to touch another bike again.....well at least not for a couple of days.