Chain guard on rear sprocket

[Bradders]

Morning. On my rear sprocket the chain guard is becoming quite loose due I think to the holes around the rivets getting larger. It’s becoming quite noisy and I’m a bit concerned about it falling off and jamming in the wheel.
Any suggestions what to do with it? Is it a case of drilling the old rivets out and taking it off? Any ides would be appreciated.
Thanks in advance.

[Matt_Harrington]

I don't have the guards on my bikes but I suppose there is no reason why you can't just give the rivets some more 'hammering'. You would need to remove the sprocket .....
It you take it off, I'll look after it for you 
Matt

[Bradders]

Hi Matt,
Thanks for your offer of looking after my sprocket guard 🙂 but I’m quite keen to put it back on. I’ll probably wait till I take the bike of the road for the winter and drill them out and put new ones in. ( although that’s probably rather ambitious for my level of mechanical skills! )

[Oddjob]

Just fit a bolt, drill out the rivets and tap to the nearest size. A bit of thread lock, just in case.

[McCabe-Thiele (Ted)]

You could always put some Honda Bond prior to assembly between the cleaned contact areas.

[Bradders]

Thanks for your replies guys. I’ve never tapped bolts before, is it reasonably easy to do?

[Laverdaroo]

dead easy, just get yourself a good you tube vid and youll be fine. Its terribly satisfying. That and get a chart showing drill sizes for various tap sizes, puts your mind at ease somewhat if youre not used to it. Just ask Siri what size drill for what ever size youre doing and a chart will come up thats really useful to keep.

[Oddjob]

Get yourself a half decent tap and die set. Metric of course. Tapping alloy is fairly easy, steel is harder and more force is required so a cutting oil is used.

I would also advise getting a chuck type tap wrench, they make keeping the tap straight a lot easier.

[Bradders]

Thanks for your advice. I shall probably leave it till the winter when I have the bike off the road and look at it then. Cheers.

[Lobo]

Bradders - you’ll be after something like this. It’s not rocket science to do, and suddenly you’ll be repairing things that didn’t need repairing - as mentioned, very satisfying.

Obviously practice on a couple of scrap pieces first…

[Oddjob]

Odd that set having only 1 starting tap but 4 finishing ones. You'd have thought all the same.

[Bradders]

Thanks Lobo, it should be fun. Mind you I have enough trouble hanging  a picture straight let alone tapping a hole straight!

[K2-K6]

Thanks Lobo, it should be fun. Mind you I have enough trouble hanging  a picture straight let alone tapping a hole straight!

For the uninitiated in this area you need to be careful in using the tap. They are whole structure of tool steel which is hard and BRITTLE by it's very concise need to cut into steel.

Plenty of lubricant and correctly sized pilot hole needs to be observed to avoid snapping it, which can make it extremely difficult to extract  (depending on location and blind hole etc) there's no option to drill them out if really compromised. Should be reasonably easy to use in an open hole as it will pass right through on a sprocket.

I feel the rivet is the correct fastener though (as did honda) and maybe worth considering resetting them to get tight. Do they go right through the sprocket or are they blind and just in from one side ?

[Bradders]

Hi K2-K6. I can see what you are saying, the last thing I want to do is mess up the sprocket. ( I’m not the most competent mechanic!). Just had a look at the sprocket and it appears the rivets go right through the sprocket.

[XS850]

Hi, yes, the rivets are countersunk on the rear face of the sprocket & dome headed on the guard side.

Bruce