Getting ready for Tour de Presteigne

Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
PS I'm a bit miffed I missed seeing the beast in action but I got there too late. Just out of interest that wasn't you torturing a bicycle helmet with a pair of metal clamps just before the tour yesterday afternoon was it?
Not me; I have the utmost respect for helmets :D . Its a pity we didn't get to meet up and say hello. I'd like to think the bike was fairly distinctive and visible - I'd even got colour co-ordinated duct tape and cable ties.

Nick
 

eddieo

Banned
Jul 7, 2008
5,070
6
Well done you! when are they going into production?

some piccys would be nice of finished bike.........
 

Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
Thanks Eddieo,

I'm posting from Germany and I don't have access right now to the few pics I did manage to take. Plenty of people were asking me to pose with the bike, so I'm sure a few of those will find their way onto the forum (or maybe onto some forum :eek: ).

Nick
 

frank9755

Esteemed Pedelecer
May 19, 2007
1,228
2
London
Well done, Nick! Looks like you swept all before you. To win by almost 40 seconds in a race lasting three minutes is pretty decisive!

I'm going to be putting together a drop-handlebar e-bike for my wife over the next few weeks, so would be interested in your thoughts on where you found it best to position the throttle.

Frank
 

Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
Hi Frank,

That was the hill climb. I thought I'd taken a wrong turning - I looked round and there was no-one else there.

I rigged up a thumb throttle on the left side. It worked out really well in use, but I had to modify the throttle casing and fabricate a special mount. I can see I'll have to create a build page or something similar to show these details.

One thing to be aware of, drop bars seem to be standardised on 24 mm dia instead of 22 mm, so just about everything you have won't fit.

Nick
 
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Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
Just found I can add a signature line to my posts.

Also, the TdP website now has some pictures.
Here's one I really like; I'll have to see if I can get a copy.



Nick
 
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flecc

Member
Oct 25, 2006
52,944
30,448
That is a great photo Nick, you're really pushing the front tyre adhesion there. :eek:
.
 

Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
Yes, I'd worked out that the race wasn't just about speed and power. Handling and cornering were going to be important on that track.

So this is with no suspension and 2.0" wide Schwalbe Marathon Supremes. The back tyre skipped a couple of times but the front held on ok.

With an electric bike you can apply power when leant over like this, but you have to wait until after the corner and you've straightened up before pedalling. Several times I was too soon and clipped the pedal on the ground.

Nick
 

frank9755

Esteemed Pedelecer
May 19, 2007
1,228
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London
That is a great picture. It really shows the speed you were going, that you have got a well balanced and designed bike, and that there was a lot of skill involved in getting it round those corners rather than (just) brute motor power.

I noted from the earlier pics that you had sensible thick tyres and they seem to have done their job too.

You're right about the handlebar sizing, so nothing designed for e-bikes fits on drops. That put me off when I thought about it last year, but now I've got a few more ideas! Thanks for your throttle info. Now I know where to look I can see it end on just under your left brake lever on the earlier picture. I've put STIs on the bike I'm building up (ie with the gear shifter in the brake levers) so I need to make sure it is out of the way!
 

flecc

Member
Oct 25, 2006
52,944
30,448
Yes, I'd worked out that the race wasn't just about speed and power. Handling and cornering were going to be important on that track.
You had that well planned Nick, and I'd already noticed in several photos that you were leaning to greater degrees than your closest competition.

Bode's second photo shows that.
.
 

Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
You're right about the handlebar sizing, so nothing designed for e-bikes fits on drops. That put me off when I thought about it last year, but now I've got a few more ideas! Thanks for your throttle info. Now I know where to look I can see it end on just under your left brake lever on the earlier picture. I've put STIs on the bike I'm building up (ie with the gear shifter in the brake levers) so I need to make sure it is out of the way!
STIs would be nice but I couldn't find any that were either affordable or for 6 speeds, let alone meeting both criteria simultaneously. I put all the gear shifting on the right hand side, which got me out of any throttle/gear conflicts.

As it was, I did the whole race on the middle chainring. The science was that the muscle power should be reserved for acceleration out of corners rather than trying to up the top speed. On that basis you could possibly stand a little conflict between the throttle and the front shifter.

Nick
 
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frank9755

Esteemed Pedelecer
May 19, 2007
1,228
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London
I think you set up the controls right. It looks like you had a thumb shifter set up on the right in the equivalent position to the throttle. Gears, throttle and front brake is too much for one hand when you are going fast, and something like a 14-28 6-speed would give you enough range for getting out of corners on what looked like a flattish course. You probably lost cadence by 25mph, but that Crystallite would have taken care of the rest!

It looks like a bike that was very well designed for the high speed manoeuverability that the course demanded. With the right type approvals there could be a fair demand for the production version - or even for a version with a legal power motor!

When Shimano first brought in STIs they were at 7-speed - they never made 6 speed ones, so you would have had trouble finding any! Agree they are the most overpriced product going, even second hand.
 

Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
It looks like a bike that was very well designed for the high speed manoeuverability that the course demanded. With the right type approvals there could be a fair demand for the production version - or even for a version with a legal power motor!
Hi Frank,

Well, I hadn't thought about a production version. I'm a researcher/designer/consultant by nature rather than a manufacturer. Between the red bike and my Torq (which also did respectably with another rider, Graham Pearce) there were a few special electronic circuits I'd built. Incidentally, I did get a few people telling me I'd done it all wrong.

The red bike has an on-road/off-road switch but I'm not entirely happy with the speed regulation. I'm making a more sophisticated one but it wasn't ready for Presteigne.

Nick
 
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