Author Topic: Throttle movement amount  (Read 365 times)

Offline paulbaker1954

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Throttle movement amount
« on: July 31, 2020, 07:58:10 AM »
A friend of mine has a UK K0 bike and I have a USA K0 bike and there is a big difference in the angle of movement from 0 to full throttle. On his UK bike I reckon it’s about 120 deg but on my US bike it’s more like 90.

The 120 movement makes his UK bike a pain to ride so was wondering if anyone knows any more.

The only variable I can think of is the diameter of the nylon bit the cable wraps round in the housing may be different
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Offline Erny

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Re: Throttle movement amount
« Reply #1 on: July 31, 2020, 08:24:25 AM »
I'm surprised there is difference - did you check spare parts catalogue what is different (or what shall be different)?
I know there are different handlebars, trottle cables, upper brake hose and wiring loom (all because of higher US bars) and switche(s).
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Offline K2-K6

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Re: Throttle movement amount
« Reply #2 on: July 31, 2020, 08:32:46 AM »
"The only variable I can think of is the diameter of the nylon bit the cable wraps round in the housing may be different"

Yes,  this is the normal part that is varied to change throttle linearity/ ratio etc.  Whether Honda produced them differently I'd not know,  but having a quick measure with a caliper should give you an insight as to what they've both got fitted to them.

I guess it's possible that one has a non std (perhaps from another Honda) fitted to make it different,  either intentionally or by mistaken substitution.

Offline Erny

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Re: Throttle movement amount
« Reply #3 on: July 31, 2020, 08:50:03 AM »
I guess it's possible that one has a non std (perhaps from another Honda) fitted to make it different,  either intentionally or by mistaken substitution.

I suspect the same
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Offline Bryanj

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Re: Throttle movement amount
« Reply #4 on: July 31, 2020, 09:03:50 AM »
 :Dthat sounds to me like the typical US owner peeing about with bits

Offline SteveW

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Re: Throttle movement amount
« Reply #5 on: July 31, 2020, 04:26:49 PM »
You can get quick action throttles for modern sports bikes, so maybe it’s something like that.
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Offline bobv7

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Re: Throttle movement amount
« Reply #6 on: July 31, 2020, 05:58:36 PM »
That's the one thing that annoys me most. It was the same when I had my 400/4; too much rotation from closed to open. Needs a throttle tube with a higher cam.

Offline Nurse Julie

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Re: Throttle movement amount
« Reply #7 on: July 31, 2020, 06:15:46 PM »
That's the one thing that annoys me most. It was the same when I had my 400/4; too much rotation from closed to open. Needs a throttle tube with a higher cam.
Agree, 400/4 throttle rotation is the worst ever, I'm sure it's not far of 360° from stop to stop. On my 550/4 it's about 180° max.
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Offline K2-K6

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Re: Throttle movement amount
« Reply #8 on: July 31, 2020, 06:35:02 PM »
"Agree, 400/4 throttle rotation is the worst ever, I'm sure it's not far of 360°"  ;D ;D ;D

It's possible that something like the 750 F2 has a different twist grip geometry that would fit and make it less travel.

Or some of the early eighties Hondas as they started to use CV type carbs with butterflies.

Offline bobv7

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Re: Throttle movement amount
« Reply #9 on: July 31, 2020, 09:56:59 PM »
That's a sound idea so if someone could do a quick measurement of the cam height and length from the handlebar there might be some relief for those suffering from over extended wrist action. Stop giggling at the back! :o

I checked mine and it's 10mm x 24.75mm near as damn it.
« Last Edit: August 01, 2020, 09:07:37 AM by bobv7 »

Offline cliff7

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Re: Throttle movement amount
« Reply #10 on: August 01, 2020, 09:27:25 AM »
Most peculiar! My 400/4 has about 100 degrees stop to stop and I'm sure it's getting full throttle. More investigation needed.

Offline Oddjob

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Re: Throttle movement amount
« Reply #11 on: August 01, 2020, 09:37:41 AM »
Same throttle pipe used by the 500K0 USA and the 500K1 England and also I may add by the 750F2, so I suspect by all the 750s.
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Offline Bryanj

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Re: Throttle movement amount
« Reply #12 on: August 01, 2020, 02:38:38 PM »
I thought they were Oddjob, just too lazy to confirm it this time

Offline robvangulik

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Re: Throttle movement amount
« Reply #13 on: August 01, 2020, 05:54:46 PM »
Most peculiar! My 400/4 has about 100 degrees stop to stop and I'm sure it's getting full throttle. More investigation needed.
On my 400 too, easy to go WOT, not even a half turn.

Offline Nurse Julie

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Re: Throttle movement amount
« Reply #14 on: August 01, 2020, 06:46:10 PM »
OK, I was exaggerating when I said I got 360° turn from stop to stop on my 400/4.....it's actually 90° 😊😊😊 It must be because I have very small hands, it just feels a lot further than ¼ turn 😁😁😁

Photo showing full extent of rotation

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