August 20, 20178 yr Hi, I've had to put a longer bottom bracket on my bike to accommodate the Pas. Now my derailleur won't extend out far enough to change into highest gear. Watched you tube videos but none show how to extend when you've reached the extent of the adjust screw? As a related question, would I be better off doing away with front gears now I have a bafang BPM rear hub?
August 20, 20178 yr Front derailleurs only extend so far. if it doesn't reach, you need a new one. Assuming a 68mm BB, I nearly always chuck the square taper cranks and the bottom bracket, and replace the whole lot with a Hollowtech one (M590). I fit the PAS on the left side so that it doesn't interfere with the gears. Those cranks, including the BB, are about £60 and it it gives you the chance to go up to 44T or 48T on the big chain-ring for relaxed pedalling at speed. The whole system is lighter, stronger, gives better gearing and gives me a reliable predictable way to fit the PAS, so it kills several birds with one stone. Also, your cranks never come loose like square taper ones sometimes do. You can run without the front derailleur. Carry a lolly-stick or similar, so that if ever you need to run with the smaller chain-ring, you can hook the chain over. it only takes a few seconds. That's what I used to do. On nearly all my rides, it's downhill on the way out and uphill on the way back, so I hooked the chain over before coming back. Once on, it doesn't come off.
August 20, 20178 yr Author Well the full story is this. Original BB u25 on my 2004 rockhopper was 17.5mm replaced yesterday with u55 127mm to make room for Pas. Would the hollow tech solve my problem with the derailleur distance?
August 20, 20178 yr Author Front derailleurs only extend so far. if it doesn't reach, you need a new one. Assuming a 68mm BB, I nearly always chuck the square taper cranks and the bottom bracket, and replace the whole lot with a Hollowtech one (M590). I fit the PAS on the left side so that it doesn't interfere with the gears. Those cranks, including the BB, are about £60 and it it gives you the chance to go up to 44T or 48T on the big chain-ring for relaxed pedalling at speed. The whole system is lighter, stronger, gives better gearing and gives me a reliable predictable way to fit the PAS, so it kills several birds with one stone. Also, your cranks never come loose like square taper ones sometimes do. You can run without the front derailleur. Carry a lolly-stick or similar, so that if ever you need to run with the smaller chain-ring, you can hook the chain over. it only takes a few seconds. That's what I used to do. On nearly all my rides, it's downhill on the way out and uphill on the way back, so I hooked the chain over before coming back. Once on, it doesn't come off. Looks like my ancient crank set is hollow tech
August 20, 20178 yr Anthony, I can send you a pedal sensor to fit to your hollotech if you want to use it.
August 20, 20178 yr Author Anthony, I can send you a pedal sensor to fit to your hollotech if you want to use it. It is very tight against the BB when the crank is fitted on the original 118mm BB . New BB is lovely and smooth running too. What does the alternate Pas look like?
August 20, 20178 yr You will lose the smallest ring because the magnet disc is lashed to it and it's not as a nice fit as a factory made leftside PAS. http://wooshbikes.co.uk/2017/hubkit/PAS-with-hollotech.jpg I hope you find a way to sort out your front derailleur. The only alternative is to file off some alloy from the left crank to accommodate the leftside PAS.
August 20, 20178 yr Author I stick with my new 127mm BB and left hand Pas . There must be a way to make it extend far enough to change into upper gear or that length BB would be useless wouldn't it?
August 20, 20178 yr There are extenders for braise on derailleurs for 78 and 100 mm BBs in many MTB online stores. They are not cheap. I carry a glove in the pannier and swap the chain over by hand when the going gets really steep. Having a front derailleur is something that interests me and I am looking to see if I can make an extender myself from a piece of aluminium or have one made by the local machine shop.
August 20, 20178 yr Looks like my ancient crank set is hollow tech Wrong type of hollowtech. This is the type I use. It's really hollow: http://www.ebay.co.uk/itm/Shimano-FC-M590-Deore-Chainset-Crankset-Triple-Chainring-9-Speed-44-32-22T-170mm-/201296084995?epid=1104289597&hash=item2ede2e8003:g:iCQAAOSwyjBW3VYu
August 20, 20178 yr Author Wrong type of hollowtech. This is the type I use. It's really hollow: http://www.ebay.co.uk/itm/Shimano-FC-M590-Deore-Chainset-Crankset-Triple-Chainring-9-Speed-44-32-22T-170mm-/201296084995?epid=1104289597&hash=item2ede2e8003:g:iCQAAOSwyjBW3VYu So that would sort my derailleur reach problem?
August 20, 20178 yr It should do, but you never know until you try it when you mix and match parts. They've always worked for me.
August 20, 20178 yr Author This bike lark is making me feel such a noob, I can rebuild marine diesels and outboards with my eyes closed but missed out not fixing bikes as a kid. Given up with front derailleur for now. Next issue is getting the rear wheel to run freely. When I tighten it up it spins but there is resistance. Is this right with a rear hub? Had quick release for so long nuts feel antiquated.
August 20, 20178 yr motor wheels engage the motor when you spin backward but should spin freely forward. If it feels sticky spinning forward then check for brake binding.
August 20, 20178 yr Author Brake caliper is off at the moment so not that. When pedaling off the ground there is what feels like a fair bit of resistance. More so when fully tightened to the frame but with no experience of hub motors I'm not sure what should feel right. When switched on it seems to power up and spin ok.
August 20, 20178 yr how many revolutions do you get when you lift the motor wheel off the ground and spin it forward by hand? 5? 10?
August 20, 20178 yr Author 2.5-3 tops. I'll slacken it off and see what I get. I did have to pack out the recess in the freewheel to keep the frame off it. Maybe one of the washers is catching.
August 20, 20178 yr Author It is upside down. Can't see anywhere externally that it's rubbing. There's no sound of rubbing. Just resistance/stiff. The wheel looks about 5mm off center in the frame away from the freewheel side. Did I read somewhere hub motors can be slightly off? Would I be better with an internal locking nut instead of packing with washers?
August 20, 20178 yr Did I read somewhere hub motors can be slightly off? that is usually sorted out by washers or dishing the wheel when you true the wheel. It can be done after a few days. The main thing is to check the anti-rotation washers. Does your wheel look like this? http://wooshbikes.co.uk/2017/hubkit/8-speed-freewheel.jpg
August 20, 20178 yr Author Yeah, the ar washer is sat on a bunch of other washers to bring it just outside the edge of the freewheel. I'm wondering if maybe one of the holes is a little large on one of the washers and its offset and touching the freewheel. When I tighten the wheel it stays off center. I was planning on replacing them with stainless ones tomorrow .
August 20, 20178 yr What about the disc rubbing on the frame or caliper adaptor? You normally need an extra washer on that side to bring the disc clear.
August 20, 20178 yr Author Disc is fine. Caliper is off at the moment because I'm waiting on a 180mm post to go with my new rotor as at 160 the caliper was grazing the hub. The more feel it the more I think it's an off center washer in the freewheel. I'll put new ones in tomorrow. How hard is truing a wheel? Am i better off letting lbs do it?
August 20, 20178 yr I'm talking about the disc rubbing on something, not the caliper. How hard is truing a wheel? Am i better off letting lbs do it? For me, it's dead simple. I do every wheel that I fit on any bike. If you give it to someone else to do, you need to give them the frame too, otherwise they might make it worse. First, you have to get everything fitted correctly. You can have a go at doing it yourself, then, if you can't get it right, give it to the bike shop to finish it off.
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