PAS Sensor disc problem

[James Lambert]

Guys,

Anyone else have this problem.

When I put the disc with the magnets on and tighten the crank back on, the disc doesnt move around, this must happen to others what do they do to get around this?

Cheers

J

 

[Deleted member 4366]

Most likely, you don't have enough clearance. Show some photos of what you've done.

 

[James Lambert]

Here are some pics:


Only thing I can think of it to take a grinder to the crank and take a few mm off, would that work:

 

[Deleted member 4366]

Yes, not enough room for it. You have two choices;

1. Take the whole bottom bracket out. measure the length and then go down to Halfords for a longer one. they cost about £10.
2. Use a file or angle grinder to remove about 3mm from that boss on the inside of your crank.

 

[Woosh]

Hi James,

You can also attach the magnet disc to the smallest chainring like this:

http://pedelecs.co.uk/forum/threads/cant-decide-what-kit-to-buy.27858/page-3#post-379350

 

[James Lambert]

Thanks guys, think I am going to grind some off the inside of the crank simply because I want to get this done, it's been taking too long.

I did try fitting on the drive side but had the same problem

 

[Woosh]

to fit on the drive side, you have to remove the magnet disc's plastic fins so that the hole in the middle is enlarged and the two halves can fit around the bottom bracket cup.
If you fit the PAS disc on the non drive side, the disc risks being kicked by your left shoe.

 

[Benjahmin]

Would glueing the disc to the crank boss work?
I had similar problems with one of those two part discs, it just didn't grip the shaft very well. So I wrapped some rubber around it and just skewered a hole through it to grip the shaft. It ain't pretty, bur it's worked since:

 

[Woosh]

Would glueing the disc to the crank boss work?

glue will crack over time.
Cableties are more reliable, you only need one so you have redundancy, you can use use 2 or 3 or 4 or 5 cableties to tie the disc to the chainring. Plus, you can grease the sensor head to stop it heating up if it comes into contact with the PAS disc.

 

[James Lambert]

Angle grinder, file and 5 cable ties later its on there and working a treat.
Will post some pics in a bit, just wanted to get this finished as it was the final thing that needed to be done before I could start using it.

 

[Deleted member 4366]

Angle grinder,

My favourite tool. I probably used one on nearly every conversion I did.