Guy Martin's Bike

Can someone please explain why guy had that convoluted multi ring set up on his speed record bike, rather than just a very big ring on the front?

So they could have another “Hope” logo on the bike.

Because the ring would be too big for his legs to fit around.

Was all to do with getting the gearing right, having one large ring the size needed to get to the speed would have been impossible to spin

I thought the ring would have been so big it would have touched the ground?

Aha this is why I’m asking……. I think the same as covert baz, but my mate thinks the same as Timmy

Was all to do with getting the gearing right, having one large ring the size needed to get to the speed would have been impossible to spin

The right gearing is the right gearing whether the gear ratio is achieved through two cogs or four. The system didn’t allow two different ratios, it was just to allow the thing to fit on the bike. Getting enough speed to be able to spin the cranks was achieved through the towing.

I’m under the impression it was designed to run the same gear as a massive ring, but in a more convenient package. So I’m with Timmy.

Bearing in mind, once it’s set up, you can probably change gear ratios with off the shelf components, if required.

Anyone else before I conceed defeat????

Defeat? What are you on about? They explained why they used that set up in the programme, that’s your answer.

Read my earlier post. Both of us had a different take from the same programme and I’m not gonna watch it again just for that.looks like I got it wrong as I thought the set up gave him some form of advantage of higher output than just using big front ring.

butcher got it right, one mahoosive ring is difficult to fit on the bike and also a PITA to amend gear size

also could be issues with shipping the chain (at 90+miles an hour!!!) and with such a wide chain angle there would be less teeth at the back sprocket meshing…

Now thats a big chainring (or is it 2 wheel drive?)

Mm, it’s purely to avoid having to fit the rest of the bike around a huge ring.

The explanation they gave on the programme – that it was somehow revolutionary and allowed him to get it up to speed more easily or something – was complete and utter bollocks.

it was an engineering solution to a given problem, both answers are right (between you and your mate)…..

I was quite surprised at the angles used on the frame – can’t remember the exact figures shown, but remeber thinking it was pretty steep at the time, more like a regular road frame.

I’d have thought they’d have slackened the head at least a little.

@rusty

Yer,
a lot of other speed record bikes have used reverse rake forks to give a large trail to avoid the twitchiness at high speed (similar effect to slack headangle).

He held it though, well done to Guy, awesome achievement.

@antimony – 26’er and 29’er on the same bike – Now there’s an idea – 650b trike anyone?

And really fast…
268.831 kilometers an hour (in the slipstream of a race car)

Slight diversion: what was the black bike in the back of his van this week during the hydroplaning motorbike attempt?
It looked like it has a big 853 or 953 sticker on it, possibly flat barred too. Intriguing as he usually rides Orange

ElShalimo – did look like a flat barred road bike – was wondering whether it was a Rourke head tube badge. Maybe a little something they built while they were doing the pacing bike?

[/url]
DSCN7250[/url] by Rourke Bikes[/url], on Flickr

It looked like a flat barred road or hybrid but it was a fleeting glance as he was doing something in his van, possibly putting his leathers on (awful boxer shorts)
The lack of Orange was probably compensated by the hope shiny bits 😛
but the big steel sticker was what made it stand out

. Intriguing as he usually rides Orange

he’s been riding a Scott hardtail at the last couple of Hit the Norths…

The black ‘thing’ in the van looked (and actually is reading the article) to be Hope’s Roukes Fixie that was at the bike shows this year…

http://www.lfgss.com/thread102560.html

I thought he had a black Mk1 Soul?

http://www.hopetech.com/page.aspx?itemID=SPG563

Interesting to see it in “just come off the beach” condition, but surely at some point they’ll have to clean it if they don’t want it to rot, at which point it will be clean and rusty.

1giant chain ring would be difficult and v expensive to produce aswell as cumbersome and a big ass sail.

I thought he had a black Mk1 Soul?

He does..or certainly did.

MBR article[/url]

Slight diversion: what was the black bike in the back of his van this week during the hydroplaning motorbike attempt?

wasn’t it the bike Rourke first built in the program to make sure they’d got the measurements right? I remember that having a big 853/953 sticker on the downtube.

Blazin-saddles link explains all

Brakes – that must be it.
Anyone with 4OD can probably confirm it

Anyone with 4OD can probably confirm it

that is it.

I thought he had a black Mk1 Soul?

He does..or certainly did.[/quote]

He was on a Soul at Relentless 24 in October, for some of the laps at least (I noticed cos so was I).

I thought the black bike was one of the ones he was training on in the push bike episode? We’ll all have to watch the pedal powered plane episode carefully and watch out for it….