Gearing enquiry
- Thread starter Benjahmin
- Start date
Ok just gave Spa cycles a call and the nice northern chap said that there's a 14-32 that is mega-range but that the 13-32 is as specced, a standard change. So I may just have talked myself out of 50 notes. Good job the mortgage is payed and it's the wife's bike, should give me some leverage for future use
So fitted the new 46t crankset. Went like dream - once I'd put the pas ring the right way round.
Also fitted one of these:
https://www.amazon.co.uk/Sks-Chainboard-Chain-Universal-Design/dp/B0019HIZBO/ref=sr_1_4?ie=UTF8&qid=1518363995&sr=8-4&keywords=sks+chainboard
Just at the start of the silver bit on top, there is a knockout which I guess is meat to accommadate a front derailleur. I put some gorilla tap inside it 'cos it's actually a weakspot. Otherwise it fits well .
Waiting for weather to tempt the memsahib out to try the new ring.
Also fitted one of these:
https://www.amazon.co.uk/Sks-Chainboard-Chain-Universal-Design/dp/B0019HIZBO/ref=sr_1_4?ie=UTF8&qid=1518363995&sr=8-4&keywords=sks+chainboard
Just at the start of the silver bit on top, there is a knockout which I guess is meat to accommadate a front derailleur. I put some gorilla tap inside it 'cos it's actually a weakspot. Otherwise it fits well .
Waiting for weather to tempt the memsahib out to try the new ring.
On my Big Bear I upgraded the original 14-28 freewheel to an 8-speed 11-40 Sunrace cassette. It required a new rear wheel and a new shifter, but was well worth doing. The gear ratio is 11-13-15-18-22-28-34-40, and so there are no large jumps between gears. Sunrace also do a 7-speed 11-34 cassette, which is basically the same as the 8-speed one but missing the 40t sprocket.
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Finally got out for a shake down ride. SWMBO reports that downhill cadence/speed much better. However we were unable to assess the climb gearing because the pas developed a fault, it was pulsing on and off. So we came home on throttle. Got the bike on the stand and stripped off the chaiguard. Found that the pas ring was slightly 'wobbling' on the shaft. At closest it was in contact with the sensor, at furthest away it was only about 2mm, but enough for motor to cut out. I noticed that the sensor body was slightly twisted compared to the chainline. Gave it the mildest of tweaks with the pliers and, hey presto, fault cured.
So it appears that these particular Woosh sensors are very sensitive and need the ring to be very close to being in contact through 360 degrees.
So it appears that these particular Woosh sensors are very sensitive and need the ring to be very close to being in contact through 360 degrees.
Yes your analysis is correct, there needs to be about 1 mm max with the KT PAS, at least the ones I have. My PAS disk mod has a gap of less than 1 mm, I was scared I was going to rub the plastic off the sensor it is so close
Bafang make a speed sensor for the BBS0x that works with about an inch of air I wish others would be inspired!
I think this one has been rubbing, at some point, because the end of the plastic sensor is chamfered.
Forecast looks good for the weekend, so hopefully will be able to get some hill climbing in.