Author Topic: 1910/11 2+3/4 Model C/D with gears ?  (Read 3117 times)

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Offline phil_h

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1910/11 2+3/4 Model C/D with gears ?
« on: 30 Nov 2015 at 15:14 »
I have the luxury of a clutch on my '13 2+3/4 so I bump it and then pop it out of gear via the clutch.
I presume that the earlier models didn't have clutches ?
What is the recommended technique for popping them in and out of gear without a clutch ?

Offline Frank Lyn

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Re: 1910/11 2+3/4 Model C/D with gears ?
« Reply #1 on: 01 Dec 2015 at 16:57 »
Not sure where the question mark goes in you subject line.  Although a two speed option was offered for the Model D, they are not common.  I ride both a C and a TS, neither with clutch. 

On the C, you pedal a bit with the exhaust valves lifted, then  drop them and (if the gods are with you), away you go at essentially full speed. It is not a very flexible engine so it works best at one speed, largely determined by the inlet valve spring tension.

On the TS, you attain forward motion (trot along side or paddle while straddled) with the exhaust valves lifted and in first gear, then drop the lifters and away you go at low speed, when ready to shift, use the exhaust lifter to remove stress on the system and go into high gear.

If by poor planning, you find yourself in neutral with the bike at a stop, Kill the engine and start over.

Try it on your '13 by ignoring the clutch.  Then you will get an idea of how these things  behave in dense traffic or uphill starts and you will praise the inventor of the clutch.


Offline phil_h

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Re: 1910/11 2+3/4 Model C/D with gears ?
« Reply #2 on: 01 Dec 2015 at 17:58 »
On the C, you pedal a bit with the exhaust valves lifted, then  drop them and (if the gods are with you), away you go at essentially full speed. It is not a very flexible engine so it works best at one speed, largely determined by the inlet valve spring tension.

On the TS, you attain forward motion (trot along side or paddle while straddled) with the exhaust valves lifted and in first gear, then drop the lifters and away you go at low speed, when ready to shift, use the exhaust lifter to remove stress on the system and go into high gear.

If by poor planning, you find yourself in neutral with the bike at a stop, Kill the engine and start over.

Try it on your '13 by ignoring the clutch.  Then you will get an idea of how these things  behave in dense traffic or uphill starts and you will praise the inventor of the clutch.

Aha. Thanks Frank.
I've never spoken about flexibility with anyone who has an atmospheric inlet engine - and never considered its 'single speed' preference. That would make for a 'less than satisfactory' outing if you went through any built-up area.
My wife and I both ride on runs so we need to ride 'complementary' bikes, so however lovely the C I've seen looks like, I don't want us to get into a situation where it feels like one of us is riding with a problem and hence spoiling it for the other - its bad enough riding these old beasts in modern situations without making it difficult before you start !

I've also only ever ridden the '13 with kaput clutch in very stressed conditions (eg brighton traffic !) so my memories of starting from a standstill are nil ;)

Offline cardan

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Re: 1910/11 2+3/4 Model C/D with gears ?
« Reply #3 on: 01 Dec 2015 at 22:19 »

Hi Phil,

Control of an early bike with no clutch is a familiarity thing. You get used to it.

In many ways the exhaust valve lifter takes the place of the clutch. If you pull it in the motor spins freely (but is not running of course) and you feel in control of the bike, say approaching a corner or a potential traffic stop. When the path ahead is clear, you drop the lifter and (with luck) the motor will fire and you're away again. If it doesn't fire immediately, usually a couple of twirls of the pedals is enough to get you underway again. Changing gear can also be helped by using the exhaust valve lifter, but practice is the most important thing, with matching engine speed to road speed the key. A clean change is a joy indeed!

Any Model C is a worthy addition to a collection. A "lovely" one is a "must have"?

Cheers

Leon