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Tested - Brompton 8-speed upgrade
Posted by: PaulM (IP Logged)
Date: May 10, 2011 10:37PM

I bought the 8 speed brompton upgrade kit from Kinetics in December. It arrived after a rather long wait. It consists of: rear wheel with sturmey archer 8 speed hub nicely built into a new rear wheel with sprocket, sturmey archer chainset, twist grip shifter and cable, modified Brompton chain tensioner. I was upgrading from the 3-speed hub and I found out from instructions on the Kinetics blog that 2 more links were required in the chain. I took the opportunity to move from 1/8” to 3/32” chain.

Fitting was a little involved. I had to cut off the glued on handlebar grips for a start. Also the head on a 3mm hex bolt for the brake lever was rounded (by the factory) and I had to drill it out. I found the instructions on the blog after starting, they did not come with the kit.

Success, it works! The gear range is very good and it's nice that first gear is the efficient direct drive. Gear 4 whirs a lot to the point where you are tempted to avoid it because of the noise, and gear 6 also to a lesser degree. However, the drag does not seem excessive. Shifting down requires that you stop pedalling, whilst shifting up can be done whilst lightly peddling.

The factory 6 speed is lighter and more efficient but requires frequent double changes, so I think the 8 speed hub is a useful alternative.

Re: Tested - Brompton 8-speed upgrade
Posted by: Geoff (IP Logged)
Date: May 11, 2011 08:45AM

Sounds good but you forgot to put 'Buy one' at the end.

n-ick will be along soon to collect his copyright fee.

"I thought of that while riding my bike." --Albert Einstein, on the Theory of Relativity

2007 ICE QNT
2008 Hase Kettwiesel AL27
2011 Catrike Trail.
1951 Engine in need of partial rebuild.

Re: Tested - Brompton 8-speed upgrade
Posted by: John Turvey (IP Logged)
Date: May 11, 2011 09:42PM

I am onto my 3rd Brompton - the first is a 5-speed (Sturmey Archer) which I converted to 10 speed by adding a Mountain Drive - this gives 10 sepersate gesrs from 17 inches to 93 inches - the top gear is higher than it was originally (larger chainwheel) and 4 lower gears (though the 17 inch gear is really too low for a 2-wheel bike - I have used it ocassionally, but have to relly concentrate on balance). The 3rd gear (direct drive) on the rear hub and the top range (direct drive) on the Mountain Drive is 62 inches which I find is a nice gear for general riding around town - the only disadvantage is the jump to or from the low range on the Mountain Drive - this really requires moving through at least 3 gears on the rear hub at the same time - so loss of momentum occurs.

My 2nd brompton is also 5 speed and has on the Neuss recumbent conversion kit - the gear range 35 to 80 inches) is not really adequate on a recumbent - not high enough in top or low enough in bottom.

My 3rd Brompton is a new 6-speed with the Wide Ratio Sturmey Archer hub giving gears from 31 inches to 94 inches - the two gears using the hub 2nd gear (direct drive) (60 inches and 49 inches) are the gears I use the most.

I do not find making double gears changes a problem, so I find the gears on my new (3rd) Brompton to be the best gearing on any of my Bromptons. (Mind, I normally ride a recumbent trike with 3 sets of gears and have to make triple gear changes at times, so double gear changes are no problem at all to me)

John Turvey

Re: Tested - Brompton 8-speed upgrade
Posted by: Donkeebrain (IP Logged)
Date: May 12, 2011 11:38AM

Quote PaulM: "It arrived after a rather long wait."

You are not unique. I ordered a pair of Birdy elastomers off Kinetics years ago & they never arrived.

Although they were to be delivered to a UK address, I was living abroad at the time & didn't have the energy to pursue Ben more than a couple of times via email.

Ben, you must know your reputation?

Re: Tested - Brompton 8-speed upgrade
Posted by: robik (IP Logged)
Date: January 20, 2012 05:16PM

Re'long wait': Kinteics had my Brompton for over a month, claiming each week that they were 'waiting for parts'. I took it back and Dales, also in Glasgow,fixed it in a day without needing parts.

Re: Tested - Brompton 8-speed upgrade
Posted by: Blair (IP Logged)
Date: January 23, 2012 08:52PM

What's the weight difference between the 8 speed hub kit and the Brompton 6 speed?

Also what are the gear ratios' in inches for the 8 speed hub? Personally I find a 17" gear very helpful in getting up hills.

Re: Tested - Brompton 8-speed upgrade
Posted by: Seamus (IP Logged)
Date: January 26, 2012 04:43PM

That H-type Brompton looks neat.

Any chance of it being reviewed in Velovsion?

Looks neat, cos it would be better if it had 20" wheels on it, wider spacing on the rear so that other hubs could fit.

20" = 406.

Re: Tested - Brompton 8-speed upgrade
Posted by: PaulM (IP Logged)
Date: January 27, 2012 07:26PM

Blair.

It's around 700g more weight for the 8spd hub compared to the 6 speed. Bottom gear is direct drive with a choice of 20,23,or25 teeth. So if you have 25T and 50 on the chainring then that's about 32 gear inches.

Re: Tested - Brompton 8-speed upgrade
Posted by: Seamus (IP Logged)
Date: June 25, 2014 11:29AM

as son as my bad brain say I can ridene new h brompton I might get a isc brake on the frony=t



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