Author Topic: Another Converted Sherpa  (Read 9649 times)

jags

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Re: Another Converted Sherpa
« Reply #15 on: December 14, 2013, 09:24:05 PM »
slick tyres will sort that out.my usual average speed is 13.5 to 15 mph on a good day.but i'm on a much lighter faster bike that you.when i had the sherpa i tried about 4 different tyres found the marathon supreams excellent.

phopwood

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Re: Another Converted Sherpa
« Reply #16 on: December 14, 2013, 09:50:08 PM »
Jags,

My tyres are continental travel contact at 690g each.  They are fairly slick.  So over my last rear wheel I have an extra 250g for the rim an extra 200g for the slime inner tube plus the weight of the hub but that may not be significant as it is in the centre. 

So I think I will start with removing the heavy inner tube and work out from there.

Peter.


jags

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Re: Another Converted Sherpa
« Reply #17 on: December 14, 2013, 10:14:35 PM »
yeah i also had travel contacts not bad but not great, marathon plus terrible, what else oh yeah panaracer ribmo  not bad but when i got the supreams  they totally transformed the feel of the bike so much smoother.only probem with them the side walls are pretty thin so off road cycling is a big no no.mind you i dont go off road much if ever.i would imaging that slime kills the feel of the tyre.yeah give Dave on this forum a shout he will advise you on a super wheel build  (daves bike shed) ;)

rualexander

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Re: Another Converted Sherpa
« Reply #18 on: December 14, 2013, 10:22:08 PM »
I didn't like the Travel Contacts when I tried them a few years ago on my previous bike, felt a bit unstable on corners, and the sidewall split after only a few hundred miles. A google images search shows the same splitting on other users tyres.

Now using Marathon Supremes on my Rohloff Sherpa.

il padrone

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Re: Another Converted Sherpa
« Reply #19 on: December 14, 2013, 10:55:38 PM »
Vittoria Randonneur Cross (26x1.75"), or Randonneur Pro (26x1.5") for more slick tread. Never had any penetration pnctures with these tyres so I rate them as good as Marathon Plus, for 30-40% less weight. I have riddent the Rando Cross on all sorts of roads, including really rough fire-trail MTB rides.

phopwood

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Re: Another Converted Sherpa
« Reply #20 on: December 15, 2013, 05:31:15 AM »
Thanks all if I upgrade my tyre they will need to be all good all year in England. Are Marathon Supreme good all year round.

Peter.

jags

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Re: Another Converted Sherpa
« Reply #21 on: December 15, 2013, 12:16:17 PM »
yes i seriously dont think you'll be disappointed .i had them on the sherpa  touring in the uk ireland france never even checked the pressure once.well i forgot to be honest  ::)
i bought mine with chainreaction only because no postage  ;)
great tyre on wet tarmac as well.

phopwood

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Re: Another Converted Sherpa
« Reply #22 on: December 15, 2013, 10:45:41 PM »
Today I changed my drag inducing slime filled inner tubes with some normal inner tubes and my Sherpa feels more like it did, just feels more alive.  In the new year I will invest in some supremes.

Thanks all for your help on this one.

phopwood

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Re: Another Converted Sherpa
« Reply #23 on: January 09, 2014, 06:25:25 PM »
All,

I was inspired by rualexander and i wanted to drop my tensioner and get a cleaner line. 

I spent a few weeks riding my bike with the standard 44 tooth chain ring.  I have now changed to a 36 tooth chainring which suits my riding much better than the 44.  The 44 was just a little high and I was using gear 9 most of the time.  By using a 36 this puts me in gear 11 most of the time.  But I have lost the speed going downhill,  I can live with a coasting downhill.

I have now removed the tensioner, I am not sure how long this will last before stretch becomes a problem, but I may put a simple push up tensioner on at that point.  Or just change the chain, they are cheap enough.

The Rohloff does feel better with no tensioner; it is just a lot smoother

All the best.

Peter

phopwood

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Re: Another Converted Sherpa
« Reply #24 on: January 09, 2014, 06:30:34 PM »
And this time with the picture.

Danneaux

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Re: Another Converted Sherpa
« Reply #25 on: January 09, 2014, 07:05:15 PM »
My, the result looks stellar, Peter; a very nice job indeed.

Wrt tensioners, the less twisting required of a chain the better in terms of reduced friction, so a push-up tensioner would be preferable to one that required double-rollers. You'd also get a bit more chain wrap in the bargain, should a tensioner be required.

Best,

Dan.

Andre Jute

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Re: Another Converted Sherpa
« Reply #26 on: January 09, 2014, 10:27:28 PM »
The Rohloff does feel better with no tensioner; it is just a lot smoother

The Rohloff tensioner may be a beautifully engineered afterthought and bodge, but it is an afterthought and a bodge all the same. It's fundamentally contrary to the principle of a "single-spewed" gear train. I reckon quite a bit of effort is justified in removing it, not least on grounds of efficiency. But I wonder if you really need to chuck out chains earlier than with the tensioner fitted. Wouldn't a half-link work?

martinf

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Re: Another Converted Sherpa
« Reply #27 on: January 10, 2014, 06:10:27 AM »
The Rohloff tensioner may be a beautifully engineered afterthought and bodge, but it is an afterthought and a bodge all the same.

I have a Surly Singleator tensioner pushing upwards with minimal tension on my Nexus 8 conversion, on an old mountain bike frame with vertical dropouts.

Agree that a tensioner with a hub gear is a bodge, but the Singleator seems to work with no noticeable friction. As I am using my old derailleur chainrings on this bike, it wouldn't be economical to fit a Chainglider, so for me the downside of the Singleator is just the minor annoyance of cleaning the single jockey wheel when I maintain the drivetrain.

Maintenance remains much easier than with the 3 x 7 derailleur system the Nexus + Singleator replaced.

phopwood

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Re: Another Converted Sherpa
« Reply #28 on: March 15, 2014, 11:12:19 AM »
All,

My conversion is running well, just one clean and a bit of chain lube since Nov last year and while it has not been  very cold it has been very wet and dirty. So I am very happy.

Have a look at the photos below and tell me do you think the chain is to loose.  It is not skipping but as I have no way to tighten the chain is this time for a new chain.  I know that I only need 1.5 mm of extra chain stay to make the chain tight, but short if filing the drop out, my only other option is a push up tensioner, but I like it with no tensioner feel and look.

Peter
« Last Edit: March 15, 2014, 11:22:36 AM by phopwood »

phopwood

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Re: Another Converted Sherpa
« Reply #29 on: March 15, 2014, 11:14:01 AM »
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