Lowering the rear by flipping the chain adjusters

[GavD]

There's always more to something than first meets the eyes isn't there!!!
I lowered the rear on my bike by rotating the chain adjuster cams at the rear of the swingarm so that the wheel spindle sits at the top instead of the bottom.

I can't remember who it was on here, but someone had reported once that the clamp part of the swingarm that hold these cams in place had cracked when tightening up the clamp with the allen head bolt. Bearing this in mind, I'd always tightened them, but not overtightened them when adjusting the chain.

To the point - when out riding today, I was getting a bit throttle happy  and all of a sudden there was alot of vibration and mechanical noise from the rear end . I pulled over fairly sharpish to find the chain was extremely slack. After a couple of minutes of "What the f*%k happened there?" I realised with the way I was running it the drive from the engine to the chain and hence to the rear sprocket is trying to turn the cams and thus loosen the chain. With the cams in their proper position it would have the opposite effect and would try to tighten the chain which would obviously be less dramatic and would have less serious possible consequences. With a lack of tools on the bike I limped the 2 miles home and sorted it.

Needless to say the cams are back in their proper place.

My initial thought when it first went was "Shit, there goes Wales next weekend ", but luckily it's all sorted and managed a 40 mile test ride, so I'm afraid you'll have to put up with us next weekend!!

[nickjtc]

That's good to know. I always assumed that the bike manufacturer made things the way they are for a reason and messing about can lead to trouble! Perhaps that is why there is no mention of changing the adjuster status quo in the manual.

[Sin_Tiger]

If you are at all concerned about breaking a clamp ring then I would be tempted to do a crack check. Who's to say what's happened prior to your ownership / stewardship. I wouldn't expect a crack if they've always been tightened to spec.

Cheapo dye penetrant test, thin down some clothes dye (red is easiest to see), clean the suspect areas with degreaser then paint the dye on, it can help to warm the area using a hairdryer (I take no responibility if she catches you  ) from behind towards the bearing end of the swing arm and keep applying until it cools. Then wipe it all down with degreaser, don't spray or pour the degreaser, just wipe with a moist cloth. Now you need some matt white paint, prefenbaly a spray, I have even seen watered white chalk powder used, as a developer. Before you paint the area make sure you have the means to clean it off before it cures, cover the suspected area and if possible force drying with a very light air stream over the surface.

A crack that might not normally be visible will usually show pretty quickly, just don't be misled by surface imperfections on a weld, a crack normally has two ends or two edges at either end that are quite distinct.

[GavD]

To be fair to triumph, on the brake caliper bracket that the wheel spindle goes through there is a small tang that stops you doing this .................. right up until the point that you get the angle grinder out of the shed!!!!!

[GavD]

If you are at all concerned about breaking a clamp ring then I would be tempted to do a crack check.

Sin,

I'm not concerned that I have a crack, I have just always been mindful not to over tighten them. Obviously last time I did the chain I was a little too mindful !! When I got home with it and checked, I had tightened them, and I couldn't move the cams myself without loosening the pinch bolts, so it was just a case of the torque overcoming the friction and moving them.

My intention by posting this was just to make other people aware really, to save the embarrassment of being by the side of the road swearing and kicking things like me today.

[Mustang]

Mrs M's steamer has had the eccentrics flipped for over 50,000 miles and has never had a chain go slack on her .
nor has the pinch bolt cracked the swingarm . 

has worn out two chain sliders (mostly the bottom run)and two rub blocks

ignition pickup senders on the other hand 
she's on #3 for the senders , fucking GILL pieces of shit

[Nick Calne]

My swingarm cracked probably due to overtightening by the garage doing a MOT but possibly something else I guess. Check it out, if I was you.

[Sin_Tiger]

Gav, yup understood. Just felt like rambling along similar lines for the sake of anyone else reading.

[Sin_Tiger]

Gav, one, directly related, thing did occur to me this morning. Have you had a look inside the bottom of the primary cover. I've seen one that was damaged from a very slack chain, hopefully you caught it early enough.

[GavD]

I was thinking something similar this morning.  Might tackle it in a bit when I've finished domestic duties. Gotta drain the oil first though.

[JayDub]

No need to drain the oil on a steamer Gav.... lean the right side against a wall (I wrap a bungee around the front brake lever too), I changed the front sprocket like that. 

[GavD]

Good news, whipped the cover off and it all looks ok in there. A few scratches here and there, but certainly no chunks taken out of anything.

[JayDub]

Excellent! See you Friday 

[GavD]

 

[Sin_Tiger]

Good news, whipped the cover off and it all looks ok in there. A few scratches here and there, but certainly no chunks taken out of anything.