Electric Brompton going strong

benjy_a

Esteemed Pedelecer
Jul 25, 2009
417
26
Been working hard and away from the forum for some time.

For any interested parties I wanted to give an update on my Crystalyte powered electric Brompton.

I have just passed 4000 miles in 8 months which I think speaks for itself really. Not wishing to tempt fate but touch wood it's still going strong as my daily 30-35 mile commuter.

I am still on the original brake blocks due to using regenerative braking (just adjusted the brakes for the first time) and I have to say that the axle nuts haven't loosened once.

The only maintenance has been regular cleaning, the bike has been used in all weather from torrential rain to thick frost.
I now only have the regen braking activating on the front brake lever. This is due to the fact that I nearly came acropper on ice the other day, tried to brake v gently, regen kicked in and the front wheel locked up! Brown trousers time but I stayed on :)

The motor is still running silently, Cellman battery doesn't seem to have lost any capacity whatsoever, Marathon Plus tyres still have loads of wear in them and I have had zero punctures.

I have had a problem with loosening spokes but I seem to have resolved this over time by regular tightening. The spokes still ping and click a fair amount and this is my only real ongoing concern. Having said that they don't seem to be getting any worse.

Can't think of much else to say really...here's hoping I get another 4000 miles without hiccups! The bike has now paid for itself and saves me £270 per month in petrol and parking.

Ben
 

neptune

Esteemed Pedelecer
Jan 30, 2012
1,743
353
Boston lincs
Hi Benjy. I am not quite clear about the regenerative braking issue. You say quote "I now only have the regen braking activating on the front brake." So are you saying that the only means of braking the front wheel is regen braking, or more likely , you meant that the regen braking is only operated by the REAR brake lever?
 

benjy_a

Esteemed Pedelecer
Jul 25, 2009
417
26
Hi Benjy. I am not quite clear about the regenerative braking issue. You say quote "I now only have the regen braking activating on the front brake." So are you saying that the only means of braking the front wheel is regen braking, or more likely , you meant that the regen braking is only operated by the REAR brake lever?

Sorry, to clarify. I wanted to be able to use the back brake in slippery conditions and not activate the regen braking which even on minimum is quite strong on the front hub motor. The regen activates on the cutout switches.

I have disconnected (just for the winter) the cutout switch on the rear brake lever. Light braking on the front lever activates the regen, a further squeeze will engage the brakes blocks. The back brake can be used now without fear of locking up the front.

Ben
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
4000 miles in 8 months is pretty impressive. I have done 4500 miles in three years.

The Cellman batteries have a great reputation. I have just built another DIY battery which I keep meaning to post details and pics of. Its 6Ah, weighs just under 2kgs and still fits easily in the back pocket of the Brompton C bag.

I am going through pads at the rate of about one full set front and back each year so about every 1500 miles.

Re having to clean the bike this winter seems to have been the dirtiest of all four ? must be because it has been so wet.

Another think to watch for is a queek that may drive you mad. Mine just started it and I tracked it down in the end to the suspension block. You need to take it off, clean the bolt through it and then regrease and re fit. Also atfer about 3000 miles one of my pedals the folding one started to click. Again required some cleaning and regreasing. Finally I have also changed the chain twice. You can get away without changing it for longer but then the back sprocket will wear and you will need to change that as well when you change the chain. They are not too expensive so its no great loss. If left too long then when changing the chain you may also have to change the front crank which makes it quite expensive.

Do you fold every day, if so has any play developed in the rear triangle ?

To test you need to have the bike off the ground and then move wiggle the rear triangle horizontally. Mine has about 2-3mm play.

Regards

Jerry
 
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benjy_a

Esteemed Pedelecer
Jul 25, 2009
417
26
Hi Jerry, thanks for all the info and things to watch out for on my bike. Do you have a tool to check if your chain has stretched or do you just measure it somehow (or just change it regularly)? I agree that the cleaning has had to be pretty darn regular, after a week the bike looks like something from a Mad Max movie! Such a testament to Brompton that it carries on and on, even in that condition; hub gears really are the answer for (proper) commuter bikes! :)

I have not got any squeeks yet but I do use teflon lubricant liberally every time I clean the bike; I really do try to take care of it as I rely on it so heavily. Pedal seems to still be OK but I have heard that the folding one can give problems.

I fold the bike at least twice a day getting on and off busy trains, I haven't noticed any play yet but I'll have a look later; I read somewhere that the bushes can be changed, do you know if that's true?

I am so pleased with the build quality and performance of the Brompton. 4000 miles with a heavy, torquey motor attached to the tiny front forks, smashing over potholes for 30-35 miles a day in all weather with another 7kg (battery) plus daily luggage in the front bag banging away and so far (touch wood) so good! I'd be surprised if many other folding 16" wheeled bikes could match this little beasty. Also, after I clean it it still comes up like new, hardly a mark on it.

Ben
 
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jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
Ben,

Yes bushes can easily be changed. Well I say easily fiddly but can be done. Just Google it. I am holding off at the moment most seem to have a lot more play before they change them.

Yes the Brompton is built well. Hub gears are the way to go for regular all year round commuting. The two speed changer on the Brompton can be problematic in the winter.

I use a chain stretch thingy just Google it. A few pounds.

Re the front carrier block check the bolts as if they come loose they will shear with that kind of front weight as per cwah's post.

Regards

Jerry
 
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benjy_a

Esteemed Pedelecer
Jul 25, 2009
417
26
Ben,

Re the front carrier block check the bolts as if they come loose they will shear with that kind of front weight as per cwah's post.

Jerry
Indeed, I saw cwah's nightmare and after reading I immediately checked my bolts! I have less weight than him on the front but checking the bolts is now part of my cleaning routine along with the axle nuts, brakes etc.

Ben
 

RobF

Esteemed Pedelecer
Sep 22, 2012
4,732
2,312
Brommies do go on and on, a dealer told me he'd never had one in that wasn't worth fixing, not least because they fetch good money secondhand, so it's worth spending even a few hundred on repairs.

A failure he'd seen a couple of time was the rear brake mount rusting through - occasional light oiling is all that's needed to prevent that.
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
The cross piece between the chain stays also corrodes.

Not on my Ti model though :p

Regards

Jerry
 

cwah

Esteemed Pedelecer
Jun 3, 2011
3,048
179
www.whatonlondon.co.uk
Indeed, I saw cwah's nightmare and after reading I immediately checked my bolts! I have less weight than him on the front but checking the bolts is now part of my cleaning routine along with the axle nuts, brakes etc.

Ben
After inspection, I think that none of my bolts came loose on both of my brompton. It was a plain metal failure due to vibration, weight and cold.

You have about half my weight at 7kg, so it may be ok. But for extra security, a little additional something to re-enforce shouldn't harm. Think of it as a torque arm for brompton bag ;)
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
The bolts do not take the weight and would only sheer if they came lose.

Fatigue is not a factor of the bolts as the main weight is taken by the welded metal lug on the frame which is shaped to fit snuggly into the carrier block. This is why it is so important to keep those bolts tightened to ensure the weight remains firmly on the welded lug and not on the bolts :p

Regards

Jerry
 
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cwah

Esteemed Pedelecer
Jun 3, 2011
3,048
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www.whatonlondon.co.uk
Maybe jeremy. Not completely convinced though. In both case, the front bag wasn't wobbling at all, but then, I did a bigger jump and BOOM, the entire bag was wobbling because of the snapped bolt.

Upon verification, the bolt that is still maintening the carrier is still bolted and I need a screwdriver to remove it.

I mean, it doesn't seem loose on removal.
 

benjy_a

Esteemed Pedelecer
Jul 25, 2009
417
26
Thought I'd resurrect this thread....my little Brompton has now passed 6000 miles and I've finally had to replace some bits.

Front tyre which was worn through to the blue protective layer (Shwalbe marathon plus). Rear brake shoes, new chain.

Incidentally I finally got around to buying a chain wear indicator tool and my old chain was so stretched that it was off the end scale of the tool! Will have to see now if I've knackered the sprockets :banghead:
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
Interesting update. I got about about 9-12 months 1500 miles plus out of my last Brompton chain before the chain tool indicated max stretch. I now clean it a little more often and am hopeful I can get more miles out of it. I have let it go longer but then found the sprocket had worn and the new chain then jumped till I changed it. At £10 chains are cheap though. For that its certainly not worth the hassle/mess of cleaning it and 12 months use is acceptable.

Sprockets are only a few pounds so no great shakes either. Of course leaving it too long and wearing the main chain ring would be more expensive.

How is your rear triangle ? I have found after 5000 miles mine has a little side ways play on the hinge which is common.

Another thing to check is your rear suspension block which gets grime in the main bolt through it and then squeaks like mad when you ride it. Just dismantle clean and a tiny bit of grease fixes it. Had me chasing that squeak for weeks till I found it lol

I have gone through two sets of front blocks and one set of rear blocks in 5000 miles.

Apart from that I don't think I have changed anything. I have tried several different tires in that time and have yet to wear any out. Initially like you I used MPs but have now settled on Kojaks or Green flash/label Bromptons.

Rims seem to hold up well, mine are wearing but still more life in them yet.

PS I did have to tighten up my front head set bearings once oh and grease the bearings on the foldable pedal.


Regards

Jerry
 
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benjy_a

Esteemed Pedelecer
Jul 25, 2009
417
26
How is your rear triangle ? I have found after 5000 miles mine has a little side ways play on the hinge which is common.

Another thing to check is your rear suspension block which gets grime in the main bolt through it and then squeaks like mad when you ride it. Just dismantle clean and a tiny bit of grease fixes it. Had me chasing that squeak for weeks till I found it lol

Hi Jerry, the rear triangle is fine on mine so far; that's with 2/3 folds per day so it's doing well.

I'm definitely sticking with the MP tyres; 6000+ miles with no punctures is pretty good (you should see the state of the tyre I just replaced - no tread whatsoever and blue bits coming through everywhere).

I have also had issues with my folding pedal; in all the winter grime and rain the bearing now feels very rough. I have tried to clean and re-grease it but not had much luck and I think that will probably be the next thing to replace. I have seen threads on repairing the pedal and replacing the bearing but I don't have the time and patience for it.

My front brake blocks are still ok, the regernerative braking is the reason I have only just had to replace one resr set at 6000 miles. Also this means the rims have no apparent wear either.

I did 35 miles on the new chain yesterday; luckily for me the sprocket and front chainring seem ok; there is no jumping at all. What's nice is that I've lost an annoying rattle - the old chain was so much longer that the chain tensioner couldn't even keep it tight and so bounced around constantly when just freewheeling. The new chain makes it feel like a new bike again :)

Ben
 

benjy_a

Esteemed Pedelecer
Jul 25, 2009
417
26
Hmmmm, further update is that under heavy load my chain does jump on the rear sprocket :mad:

So, can anybody give me a little pointer as to how to change it? How does one remove it from the rear wheel?

Also there seem to be two types of 3 speed and I'm not sure what I need. My bike is a standard M3L and the hub is a BSR.

The two options are a 13 tooth sprocket for an SRAM or a 3 spline Sturmey Archer. I'm guessing I need the Sturmey Archer?

Thanks,

Ben
 

shemozzle999

Esteemed Pedelecer
Sep 28, 2009
2,826
686
Hmmmm, further update is that under heavy load my chain does jump on the rear sprocket :mad:

So, can anybody give me a little pointer as to how to change it? How does one remove it from the rear wheel?

Also there seem to be two types of 3 speed and I'm not sure what I need. My bike is a standard M3L and the hub is a BSR.

The two options are a 13 tooth sprocket for an SRAM or a 3 spline Sturmey Archer. I'm guessing I need the Sturmey Archer?

Thanks,

Ben


Check out the maintenance videos Ben:

Brompton Bicycle


The BSR [Brompton Standard Range] is an updated version of the classic Sturmey Archer hub

and here for sprockets:

http://www.brompton.co.uk/spares/t7/rear-sprockets-and-spacers
 
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RobF

Esteemed Pedelecer
Sep 22, 2012
4,732
2,312
Benjy's doing several thousand miles a year on his Brompton - not many bikes would stand that.

The transmission is said to be a weak point, although my Nano has a front hub motor which should take some of the strain.

For what it's worth, I think 'BSR' on the gear hub stands for Brompton Standard Range, my six speed is marked 'BWR' which is Brompton Wide Range.

The six speeds are achieved by two sprockets on what I believe is the same three speed hub.

If so, it's a Sturmey Archer.

I would take the bike to a Brompton dealer and let them source the sprocket.

Another good thing about Bromptons is every component is available from Brompton as a spare part.

On the subject of rear triangles, I'm told the bridge on which the brake calliper is mounted can be prone to rust.

Worth keeping it clean and lubing it occasionally.