Glue that can withstand the heat of a brake rotor

**Macstar** · 26th November 2007, 16:33

Hey'all

Have you ever asked the shop attendent at Mitre 10 or Repco etc for technical advice...?

Can someone please let me know if they are aware of a brand of glue that will bond metal to metal (i.e. a speedo magnet to a disc rotor) and that can withstand super hot temperatures?

Cheers.

**geoffm** · 26th November 2007, 20:02

Epoxies let go around 60-70 degrees. You woul be lucky to get more than that with glue. Put the magnet further away from the dis, on a rim or on the sprocket?
For the on bike data aquisition system i was playing with at one stage, the spricket was the best place
Geo

**crazefox** · 26th November 2007, 20:06

yeah mate i got just the shit its called panel glue we use it at work for glueing new panels on cars insteed of welding.F##KING strong

**Macstar** · 26th November 2007, 20:13

My locktite is good up to 160 degrees celcius apparently, and I have tried using some of this for now. The cable for the sensor is not long enough to reach the rear sproket.

I'll look into this "Panel Glue" but again it's heat, not sticknesses that I'm worried about.

Cheers.

...And upside down KTM forks would prevent mounting it anyway but the disc rotor.

**marty** · 26th November 2007, 20:20

metalset is good for high heat, but i would say that brake rotors would get too hot.

why can't it go on the rim? one way of avoiding glue would be to drill into the rotor, and use a hammer-in rivet to secure the magnet.

**Macstar** · 26th November 2007, 20:27

Originally Posted by marty

metalset is good for high heat, but i would say that brake rotors would get too hot.

why can't it go on the rim? one way of avoiding glue would be to drill into the rotor, and use a hammer-in rivet to secure the magnet.

Yeah I looked Metalset up (80 degrees C). I have upside down forks that offer no attachment point for the sensor to read a rim-mounted magnet.

Drilling and hammer'n I reckon.

Thanks.

**Ixion** · 26th November 2007, 21:36

JBWeld is rated to 500 F about 260C . You can get it from trademe and probably other places

**Warr** · 26th November 2007, 23:56

I tried a magnet mounted on the disc. It didnt work too well as the pickup picked up extra pulses off the mounting screws.
Best place it to glue the magnet onto the rim. I didnt use the magnet that came with the unit I used a piece of hard drive head magnet. I broke a piece off in a vise and put it into some heat-shrink, heated it and then used some 2-pot glue to attach to the rim. All worked sweet.

**Pancakes** · 27th November 2007, 09:21

Originally Posted by Warr

I tried a magnet mounted on the disc. It didnt work too well as the pickup picked up extra pulses off the mounting screws.
Best place it to glue the magnet onto the rim. I didnt use the magnet that came with the unit I used a piece of hard drive head magnet. I broke a piece off in a vise and put it into some heat-shrink, heated it and then used some 2-pot glue to attach to the rim. All worked sweet.

There's your answer, install or magnetise your mounting bolts and divide the wheel circumference by the number of bolts? Will increase your resolution too.

Or swap the sensor out for an optical pickup? It is just an on/off pulse.

Or use a Hall effect sensor and the gaps in your rotor?

**imdying** · 27th November 2007, 10:56

JB weld or Araldite, it won't fall off due to heat.

**Macstar** · 27th November 2007, 14:59

That JB weld stuff looks like the go. $12 on trademe and up to 300 degrees celcius. I'll let you know you good it is in a few days...

Oh yeah, and I did put two magnets on and divide the total wheel circumference as someone suggested, it gives a more reliable reading.

Thanks again fellas

**Warr** · 27th November 2007, 16:02

Originally Posted by Pancakes

There's your answer,
1) install or magnetise your mounting bolts and divide the wheel circumference by the number of bolts? Will increase your resolution too.

2) Or swap the sensor out for an optical pickup? It is just an on/off pulse.

3) Or use a Hall effect sensor and the gaps in your rotor?

Nothing theoretically wrong with any of those options apart from
1. Push bike speedo wheel circumference didnt divide down that far.
2+3. Would all have needed external power, and not readily available off the shelf.
But granted extra sensors could be the go, however the upper speed range of most pushbike speedos is 200k's, the limit I figure being something to do with how fast the reed switches can operate. If you have more sense points this would reduce the max speed.

**Taz** · 27th November 2007, 16:10

www.dirtbike.co.nz do a range of magnets for speedo's. One's that replace a rotor bolt or fit into a 3/8" (10mm) hole. Maybe these would be better?

**Macstar** · 27th November 2007, 16:24

Ah man, I bought the glue already! Those magnetic bolts are $18 a piece though...

My Koso speedo can take up to 6 sensors, you just divide the total wheel circumference by the number of sensors and then enter them in to the speedo unit, thus the top speed is not affected.

P.S. I tried a bicycle wireless speedo before on my KTM before the Koso but it was hopeless. The top speed was less than 100kph and there was serious lag time between the sensor and displayed speed on acceleration or braking. One second you're doing 10kph, the next you're doing 30kph.

**Warr** · 27th November 2007, 16:41

Originally Posted by Macstar

Ah man, I bought the glue already! Those magnetic bolts are $18 a piece though...

My Koso speedo can take up to 6 sensors, you just divide the total wheel circumference by the number of sensors and then enter them in to the speedo unit, thus the top speed is not affected.

P.S. I tried a bicycle wireless speedo before on my KTM before the Koso but it was hopeless. The top speed was less than 100kph and there was serious lag time between the sensor and displayed speed on acceleration or braking. One second you're doing 10kph, the next you're doing 30kph.

Do you have a link for your speedo... my search had alot of scooter stuff ??