Topic: reset knob on speedometer

[flatlander]

i somehow lost that little black plastic thing for zero-ing the kilometre counter on the speedo. no idea how or when… guess it was not properly attached and i never thought to check.

having had a look around there seem to be mainly 2 kinds: those that attach with a screw from the side, and those with screw from the top (or bottom, with the speedo mounted).
looking at the thread on what remains of mine, i assume it was the “top-screw type”.



now i have this damaged speedo that has such a knob attached.
problem is that the cross screw head is complete worn out. drilling it out could be an idea but the bloody thing is built so that it turns, so would just keep twisting with the drill constantly resetting the kilometres and not go anywhere.



any ideas for what to do with this?
use a small clamp (instead of a vice) to hold the plastic knob while drilling, hoping that  it both holds strongly enough to drill out the screw, and gently enough to not break the plastic?
or just stuff it and find some other piece of plastic that can be used instead?

it's a ridiculous little thing to be worried about, i know, but i like to use the counter to keep track of when i should refuel. easier than doing math and trying to remember!

[Black 750K8]

First start soaking it with PB Blaster. You can use a small burr bit in a dremel tool and carve a slot in it for a flat head screwdriver. If you don't have a dremel get one they have a million uses for small stuff like this. When you get the slot cut get a screw driver that fits tight Line it up and tap on the handle a few good times BEFORE you try to turn it hold the black part with needle nose gently. If it does not turn soak it more for another day don't rush it.

[flatlander]

thanks, i might give it a try with a dremel. it may also cut into the plastic thing as the screw is recessed but may be the only feasible option. i think trying to drill it out would probably cause more damage.

[flatlander]

i don't seem to be able to get pb blaster here so i used creep oil for 4 days. then took the dremel to it.
the slot looked good to start with but the remaining material on the head of the screw was too thin and it broke when trying with the screwdriver. so that didn't work...
now i made another cut with the dremel, across the first one and broke off whatever was left of the screw head. should be able to pull of the plastic thing now but it's very tight so now i let it soak a bit more with creep oil, this time from the other side. hope this will get it off eventually.

[martin99]

On my old F2 I had to remove the tripset knob, which was on the side, to be able to dismantle the gauges. I ended up cutting it off because no matter what I did it wouldn't play. No worries I thought, I'll just get another one later and screw it back on. Big mistake. When I examined the 'thread' more closely, I realised it wasn't a thread at all, rather the spindle had been cut/shaped around it's circumference giving the impression it was threaded. I concluded they did this before moulding or pressing the knob on, to prevent it from being pulled or vibrating off. Might be off here, but I'd take a closer look at that thread or even try to screw a nut on it. I also find it rather strange that the screw holding the knob on your spare speedo is completely worn out, not the sort of thing you would dismantle too often. Sure it's not been peened over like a rivet?
Apologies in advance if I'm talking crap

[Don R]

Check with Lecram, he has the ad to the right some of the time. I'm sure he has the old ones might have yours too.

[flatlander]

oldskoonuts: it did look like a worn-out cross head but you're right, strange that somebody would have tried removing it before. anyway, head's been chopped off now so i'd expect the pastic thing to come off if it's put together the way i think it is. of course i might be wrong!

don r: thanks a lot, that's a good idea. i'll give him a shout after one more try to pull that thing off.

[flatlander]

in the end i couldn't get that knob off the old speedo, gave in and ordered a new one from cb750faces.com
it seemed expensive for what i thought was a piece of plastic but i was so fed up that i got it anyway. nice suprise: it is made from a solid piece of aluminium, well worth the money if you're stuck and need one.



the hole in it is 3mm, the spindle on mine is 4mm. so had to drill it up a bit, then it fit.



this one is much shorter than the original one but it works, you can turn it with one finger. think that's not too bad?



[i know... i know... the rusty bits. that's for another time!]