[GUNR]

Here's a picture of the chain was I just swapped out for a new Renold. The stamp is either 'Rolon' or 'Olon' with a capital 'R' encircled preceding (maybe some sort of copyright?).
Does anyone know who makes this chain? As it happened, the old chain was not only 'in spec' but had an identical '21 pin to pin' measurement as the new Renold. A good reason to keep the old one as a spare...

[Onurag Chatterjee]

Hi GUNR!

It is indeed 'Rolon'.

They are a well-known chain and sprocket manufacturer based in the southern-Indian city of Coimbatore.

Rolon is the OEM for many motorcycle brands in India.

[GUNR]

Hello Asian Onurag,
Thanks for the info about the chain.
I recently changed mine to a Renold and about 3 weeks later there appears a Facebook ad for a low mileage Bullet which had thrown its primary chain. The crankcase was a mess so I’m pleased I took the advice of the guys here and did it before it was too late.

[Onurag Chatterjee]

Better safe than sorry!

That issue seems common among GT535 owners in developed markets where average, highway-cruising speeds are much higher than in RE's home-market of India.

I'll update the maintenance document with this input. Thanks!

Did you buy the replacement primary chain from Hitchcocks?

[axman88]

That issue seems common among GT535 owners in developed markets where average, highway-cruising speeds are much higher than in RE's home-market of India.

I thought that the primary chain failures were more a result of the overly aggressive automatic chain tension adjuster on the whole UCE series, than due to sustained rpms or overheat or whatever would be related to highway speeds?  I'd like to hear more about the thoughts behind this average speed related failure theory.

Like a lot of folks here on the forum, I took the "auto" out of my C5's primary tension adjuster, by removing the compression spring.

[Onurag Chatterjee]

I thought that the primary chain failures were more a result of the overly aggressive automatic chain tension adjuster on the whole UCE series, than due to sustained rpms or overheat or whatever would be related to highway speeds?  I'd like to hear more about the thoughts behind this average speed related failure theory.

Like a lot of folks here on the forum, I took the "auto" out of my C5's primary tension adjuster, by removing the compression spring.

It was more of a guess than a conclusion based on scientific testing, I'm afraid.

I'm Indian and a member of several FB and WhatsApp groups for owners of Royal Enfield's UCE-engined 500 and 535.

The bulk of these machines' owners are in my country, yet such cases of tearing primary chains are quite rare here. On the other hand, the same complaints from developed markets like UK, France other parts of Europe and the US are fairly common.

Here, most RE's are only ridden between 80 and 100 Kmph on the best of highways. While 105 to 120 Kmph (65 to 75 MPH) is the norm in places like the US, the UK, Australia and Germany.

Hence, I assumed the co-relation. However, co-relation doesn't equal causation, so you are likely right.

[axman88]

It was more of a guess than a conclusion based on scientific testing, I'm afraid.

Here, most RE's are only ridden between 80 and 100 Kmph on the best of highways. While 105 to 120 Kmph (65 to 75 MPH) is the norm in places like the US, the UK, Australia and Germany.

Hence, I assumed the co-relation. However, co-relation doesn't equal causation, so you are likely right.

Perhaps there is a relationship, in that sustained high speed could result in higher engine temperature.  Also, chain tension increases with higher chain speeds due to the centrifugal effect.  Either/both of these would increase chain length, and perhaps allow the tensioner to take up another tooth.

I'd guess that it's when the chain tries to return to it's cold / stationary length that the chain tensioner would do the damage.

Thanks for bringing up the geographical aspect.  It only helps with understanding the issue.