The Black Beast returns

[Mulger bill]

Richard, the Deore/LX group you got had prolly 7000-9000 km on them over a bit less than two years when I got all excited over SRAMs XGen triggers. IIRC it was still shifting well on worn 22-32-42 Shamino rings when I swapped out. It's been in a box in the shed ever since. Could I have stuffed it when cleaning it before posting?

Blybo, that LidLED looks better than the bodged white blinky I run, and the integrated reds seal the deal, which of the listed shops on the site had it?

Shaun

[europa]

Richard, the Deore/LX group you got had prolly 7000-9000 km on them over a bit less than two years when I got all excited over SRAMs XGen triggers. IIRC it was still shifting well on worn 22-32-42 Shamino rings when I swapped out. It's been in a box in the shed ever since. Could I have stuffed it when cleaning it before posting?

That's pretty much what I thought - not enough to say 'definitely rooted' but enough to justify a good look and clean up. I still reckon it's must not pulling over far enough as discussed, but this does give something else to do. Looks like I get to discover the secret life of front drs soon

Richard

[Blybo]

Blybo, that LidLED looks better than the bodged white blinky I run, and the integrated reds seal the deal, which of the listed shops on the site had it?

Shaun

I found it at Brunswick Street cycles, $29 IIRC. It is a blinky only but is bright enough to notice it light up walls 15-20 metres away and you wouldn't want to look directly at it in close quarters. I didn't even check that list as I already had 1. We got one for the missus too as the group rides we are starting to go to mean leaving home at 0530, still pitch black. Although my cateye is good for bike paths and to be seen, I'm getting sick of hitting potholes and changes in surface too whilst at the higher downhill road speeds so AyUp's are on the cards.

Sorry to drag things off topic Richard. IIRC the Specialized ergo grips were about $25 and there is also a BBB version which would probably be cheaper. Shouldn't be too hard to track down in Adelaide.

[heavymetal]

Interestingly, while the chain was refusing to shift, I could see the dr pulsing from side to side. There are two issues here - what was causing the sideways movement in the chain and why didn't the dr just pull the chain across?

I didn't know my old Sora FD had landed in Adelaide after I threw it away in disgust.

Isn't the DR mounted on a rubber shim? Maybe it's part of the cause of the problem.

Kev.

[europa]

Isn't the DR mounted on a rubber shim? Maybe it's part of the cause of the problem.

Kev.

Nah, we're talking a much bigger movement than that. The interesting thing is, there's no warp in the chainring so I've got no idea what's causing it. There is a removable link and I can't say I'm as impressed with that (a connex) as you lot seem to be, but the pulse is happening far more than once a chain revolution so it's not that.

Just another weirdness sent to annoy me

Richard

[Mulger bill]

Can you see the deflection spinning the cranks by hand in your stand?

Here's a thought, take a video cam along on a ride and film what's happening, I'm sure Toni Pearon could use the footage

Shaun

[Kid_Carbine]

If the chainring runs true, then we can rule out bent B/B axle, ill fitted crank, bent spider & warped chainring.
[The crank really is 'secure' on the axle, ..... isn't it?]

This leaves us with several possibilities.

Bottom bracket flexing under pedal strokes.
This would give you two oscillations per cycle. It would also give you the heeby geebies if the frame was so frail that it was moving around noticeably at modest power outputs.


Seat tube flexing.
If that's it, then get real worried real quick.

Movement of the cage, but not the whole front Dérailleur [including clamp] caused by varied tension of the cable.
I don't remember where your shifter is located, but if it's on the bar then there could be connected to this problem.
If it's on the down tube then Houston, we have a problem.

[europa]

Bar shifters.

I wouldn't have thought it was cable tension, but it's something else to look at.

I'll get to it, probably not quickly but I'll get to it.

Richard

[MountGower]

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[kukamunga]

...I can't say I'm as impressed with that (a connex)

Yeh. Melbourne cyclists aren't too impressed with Connex either......

Bin the Bike Ban