Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet with the UCE engine => Topic started by: ofi on July 30, 2020, 04:56:09 pm

Title: Chain tensioner Bolt leaks
Post by: ofi on July 30, 2020, 04:56:09 pm
Hello,

my name ist Oliver and I live in Germany. Please excuse my bad English.

I bought a Bullet Classic from 2009 this Sunday and I am very happy with it.

Unfortunately, oil drips from a screw that I think is the chain tensioner.

Can I just unscrew and seal the screw without the inside falling apart?


Thank for your help.
Title: Re: Chain tensioner Bolt leaks
Post by: Haggis on July 30, 2020, 08:00:19 pm
Looks like someone has changed the automatic adjuster for a manual version?
When you take out the centre bolt there is a spring that pushes up a plunger to tension the primary chain.
(https://i.ibb.co/MkkdHLB/RE-EFI-Oil-Change-noted.jpg)
(https://i.ibb.co/DgTqNDz/IMG-20190211-145500.jpg)
Title: Re: Chain tensioner Bolt leaks
Post by: johno on July 30, 2020, 08:10:12 pm
The 2009 should have the auto chain adjuster, that bolt should be tight to set the slipper against the chain, this would stop the leak as well.
here is a new one.
https://accessories.hitchcocksmotorcycles.com/20011?qty=1&continue_url=https%3A%2F%2Fwww.hitchcocksmotorcycles.com%2Fpartsbook-pages%2F2127
Title: Re: Chain tensioner Bolt leaks
Post by: ofi on July 30, 2020, 08:47:11 pm
Thank you for your answers.

I have ordered a new tensioner.
According to the pictures, I can change the tensioner without removing the cover of the primary chain.
The correct tension will be set automatically with the new one.


Title: Re: Chain tensioner Bolt leaks
Post by: gizzo on July 30, 2020, 09:29:24 pm
Yes. But make sure you take the cap and spring out of the new tensioner and retract the extendable pin (release the ratchet mechanism or you won't be able to do this) before you install it. Once the tensioner is installed, then fit the spring and the cap. Otherwise you'll be trying to fit a fully extended tensioner.
Title: Re: Chain tensioner Bolt leaks
Post by: Ove on July 30, 2020, 10:27:13 pm
That's an odd thing to remove. Could there be a reason it was taken off?
Title: Re: Chain tensioner Bolt leaks
Post by: Haggis on July 30, 2020, 10:44:21 pm
Maybe took the bolt out and lost the spring?
When you refit the new one the word "Pricol" should be on the inside, towards the engine.
You should not have the ratchet mechanism facing out.
The one in my second photo is in the wrong way round.
This is the correct way round,
(https://i.ibb.co/K6y2bW6/IMG-20190211-151151-1.jpg)
Title: Re: Chain tensioner Bolt leaks
Post by: gizzo on July 31, 2020, 12:12:40 am
Does it make a difference? Only asking because it looks symmetrical and that it'll fit either way but in my GT the frame tube clearance only lets it fit one way.
Title: Re: Chain tensioner Bolt leaks
Post by: Haggis on July 31, 2020, 12:38:19 am
Not symmetrical,  the plunger mechanism is offset to one side. If you fit it with the writing outwards the plunger pushes on the edge of the tensioner blade. This gives uneven pressure on the blade as you can see by the wear marks. If you fit it the other way it pushes on the centre of the tensioner blade.
(https://i.ibb.co/cNkwDmM/IMG-20190213-204909.jpg)
(https://i.ibb.co/FwQ6by4/Pics-Art-02-12-11-56-50.jpg)
(https://i.ibb.co/KWLxjSF/IMG-20190214-111039.jpg)
Title: Re: Chain tensioner Bolt leaks
Post by: gizzo on July 31, 2020, 01:14:03 am
I see. Thanks.
Title: Re: Chain tensioner Bolt leaks
Post by: Frogman8 on July 31, 2020, 06:54:04 am
Haggis
Extremely detailed and useful pictures. Thanks for archiving and levelling them for ease of understanding. This is what makes this such a great place.
Title: Re: Chain tensioner Bolt leaks
Post by: Joe_535i on July 31, 2020, 08:41:58 am
That's an odd thing to remove. Could there be a reason it was taken off?

There have been cases of snapped primary chains and exploded engine housings. People on Enfield forums started replacing the primary chains and building own chain tentioners to avoid having a fatal engine failure. While rebuilding my engine I realized that between the crank drive side bearing and the drive sprocket there is a spacer, if anyone misses to assemble that (factory, workshop) than the sprocket and clutch basket are not alligned properly. This is more likely to snap the chain than anything else IMO.
Title: Re: Chain tensioner Bolt leaks
Post by: Haggis on July 31, 2020, 09:28:41 am
Caught one my primary chains just in time.
(https://i.ibb.co/fFHgSQq/55576022-10219617976743940-4344763335808385024-o.jpg)
Title: Re: Chain tensioner Bolt leaks
Post by: Guaire on July 31, 2020, 02:56:59 pm
Excellent!
Title: Re: Chain tensioner Bolt leaks
Post by: Ove on July 31, 2020, 03:52:18 pm
Caught one my primary chains just in time.
(https://i.ibb.co/fFHgSQq/55576022-10219617976743940-4344763335808385024-o.jpg)

Thanks for the explanations and photos. Excellent. What sort of mileage was on the primary up to this point?
Title: Re: Chain tensioner Bolt leaks
Post by: Rattlebattle on July 31, 2020, 05:26:34 pm
I replaced my original chain with a Renolds early on. Haynes mentions being sure to refit the tensioner the right way round and that some were installed incorrectly at the factory. I’m inclined to agree that alignment is crucial. The crankshaft spacer is chamfered and also needs to be refitted the right way round.
Title: Re: Chain tensioner Bolt leaks
Post by: heloego on July 31, 2020, 06:16:23 pm
"...installed incorrectly at the factory."
   Imagine that.  ::)
Title: Re: Chain tensioner Bolt leaks
Post by: Joe_535i on August 01, 2020, 09:39:55 am
... pointing out a mistake made by the factory.

Imagine that.  ::)

I guess I have some issues with my center stand too.
Title: Re: Chain tensioner Bolt leaks
Post by: gizzo on August 01, 2020, 10:48:59 am
... pointing out a mistake made by the factory.

Imagine that.  ::)

I guess I have some issues with my center stand too.

I can sit on my bike and roll the bike off the stand now. Not have to chock the stand with the back of my boot to stop the bike skidding along. Nice.
Title: Re: Chain tensioner Bolt leaks
Post by: Joe_535i on August 01, 2020, 01:43:43 pm
I can sit on my bike and roll the bike off the stand now. Not have to chock the stand with the back of my boot to stop the bike skidding along. Nice.

To lazy to do anything about it.  ;)

The company better gives someone a job who knows a thing or two about stand ergonomics.
Title: Re: Chain tensioner Bolt leaks
Post by: Jako on August 02, 2020, 12:32:27 am
I would be removing the side case and checking or replacing the primary chain and checking the clutch retaining nut and crank  end bolt are tight as these are a known  issue.  Its a easy job to remove the side case and worth an inspection for peace of mind . You can then also inspect the chain tensioner .