Pro Connect Gears - Pedelec Forums

tillson · #1 (**permalink**) 21st July 2008, 19:00

I am finding that my Pro Connect is occasionally making a nasty banging noise from the drive system. This is accompanied by a judder on the pedals. It usually happens in the range 3rd to 6th gear. I think it is the gear hub slipping. Also, I sometimes detect that the gear ratio has changed without me making an input on the selector. I have had a look at the gear selector cable and in 1st it is completely slack with a fair amount of free play. The cable moves the cam on the gear hub with each click of the selector all the way through to 8th. I know nothing about setting up these gears and there is no information in the manual. I suspect that the cable might be slightly out of adjustment and the gears aren’t quite full engaged. Can anyone point me in the direction of gear setup information for this hub please? Or offer any opinion / advice?
On a more positive note, I collected my Pro Connect last Friday. So far, I am very impressed. After initially charging the battery when I got it home, I went out for a ride to run it right down as part of the "conditioning" exercise. After doing 36 miles of riding around a hilly part of Derbyshire in Standard Mode, it finally ran out. I am very impressed by this, I was actually expecting it to do between 20 and 25 miles.
I quickly find that my legs are going like bee’s wings, so I think a smaller cog (16 tooth) on the hub will be required before too long. What is this likely to do to the range of the bike based on the above?
Thanks in advance for any help.
Tom

HarryB · #2 (**permalink**) 21st July 2008, 19:31

Try checking the chain tensioner for up and down movement. If it is sticky it allows the chain to slip on the rear sprocket - a little bit oil on the pivot will cure this. Lowering the gearing makes a surprising dent in the range in my experience (about 10 miles less on my commute).

flecc · #3 (**permalink**) 21st July 2008, 19:56

The problem is almost certainly what Hal has described as this has been happening on a number of the new bikes, just the tightness of the new pivot on that tensioner. If that doesn't solve your problem, post back since it could also be a very slight gear cable adjustment needed.

If you go right down to a 16 tooth sprocket you'll probably find the range slumps to what you originally thought, 20 to 25 miles. The reasons are that the change increases the range of speeds over which full power is applied, and also extends the application of power from a limit of 15 mph up to around 20 mph.
.

JamesC · #4 (**permalink**) 21st July 2008, 20:16

In gentle rolling countryside, I am getting about 30 miles on the 50% middle setting with a 19T sprocket. My best was 38 miles when still using the original 23T.

James

tillson · #5 (**permalink**) 21st July 2008, 21:02

Thank you for the replies. I see that lowering to a 16 tooth sprocket has quite an impact on range. I think I will lower it, but not to 16. My trip to work and back is 18 miles, so I'll probably go for 18 or 20, if they make such a thing.

I have just checked the tensioner and it seems to be free. It certainly does not stick and moves smoothly when I apply presure to it.

Do I need to adjust the cable? If so, how do I do that?

Thanks again.

Tom

flecc · #6 (**permalink**) 21st July 2008, 21:14

With sprockets you can have any number of teeth from 16 to 24 Tom, and I think 19 is a good compromise for the Pro Connect to retain good range.

It's normal for the new gear cable to stretch slightly initially, and it probably only needs the slightest tweak. Where the cable outer leaves the handlebar changer there's a screw out socket that the outer sits in. Just screw it out a touch and test at that. It's easily tweaked on the road to get it just right.
.

tillson · #7 (**permalink**) 21st July 2008, 22:07

Thanks Flecc, I'll give it a go tomorrow morning. I think the spurious changes of gear ratio point towards the cable needing a very slight tweak.

Kind Regards

Tom

50cycles · #8 (**permalink**) 21st July 2008, 23:43

Hi Tilson

Please make sure that you stop cycling when changing gears.

It is the opposite to chainging gear with a derralieur system.

Hub gears really do not like hard peddaling when changing.

Best regards

Scott

JamesC · #9 (**permalink**) 22nd July 2008, 11:33

Quote:

Originally Posted by tillson

Thank you for the replies. I see that lowering to a 16 tooth sprocket has quite an impact on range. I think I will lower it, but not to 16. My trip to work and back is 18 miles, so I'll probably go for 18 or 20, if they make such a thing.

I have just checked the tensioner and it seems to be free. It certainly does not stick and moves smoothly when I apply presure to it.

Do I need to adjust the cable? If so, how do I do that?

Thanks again.

Tom

For ProConnect users, here is a link to the Shimano Technical Service Instruction leaflet that covers the gear arrangement on the ProConnect.

Specifically, the Alfine SL-S500 RapidFire lever shifter which is connected into the Nexus 8 hub (via the Cassette Joint CJ-8S20).

James

tillson · #10 (**permalink**) 23rd July 2008, 11:03

Thanks for the tips / info. I must admit that I had not ridden a hub gear bike for many years and my gear changing technique probably wasn't quite right. I haven't made any adjustments, just followed Scotts advice and things are much better, but I still do very occaisionally get the clunk and judder.

Whilst having a poke around the bike, checking various bolts for tightness etc, I have noticed that the front chain sprocket has a bit of float in it. If I take hold of it, I can move it a few mm with my fingers. Is this normal? I have never noticed it before on any other bike I have owned.

Regards

Tom