Author Topic: Gear changing  (Read 352 times)

Offline brodsord

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Gear changing
« on: February 29, 2020, 04:13:46 PM »
Hello everyone,

Could anyone shed some light on why my CB750 k5 engine won’t shift gear with massive pressure on the shift lever when the engine is running?
When the engine is not running the lever shifts through the gears smooth.
I’ve been putting this bike together over last few months, it was just a frame and engine when I got it, engine itself runs great, today is the first day I’ve got her out so I’ve only Just discovered this.
Thanks for any help


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Offline brodsord

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Re: Gear changing
« Reply #1 on: February 29, 2020, 04:15:08 PM »
Without massive pressure*


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Offline Johnwebley

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Re: Gear changing
« Reply #2 on: February 29, 2020, 04:40:26 PM »
What's the clutch like?

Could be dragging.



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Offline brodsord

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Re: Gear changing
« Reply #3 on: February 29, 2020, 04:45:54 PM »
Hi John,
There’s a bit of a rattle coming from the clutch area which disappears when lever is pulled in.
When you actually put her into gear the clutch is working correctly from what I can see.

I forgot to mention in post, a few weeks back when I got her first fired up, the drive chain want fitted and she clicked through the gears ok, although there was a bit of noise in forth and fifth gear, sounded like a rattle.


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Offline brodsord

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Re: Gear changing
« Reply #4 on: February 29, 2020, 04:46:49 PM »
Wasn’t fitted*
F@cking auto correct


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Offline Johnwebley

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Re: Gear changing
« Reply #5 on: February 29, 2020, 04:57:36 PM »
Wasn’t fitted*
F@cking auto correct


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I know. Bloody nuisance.


Put it on the stand.rear wheel in the air. With the engine running. Engage all the  gears.

Ideally you sit on it.pull in the clutch. And operate rear brake.

Does the wheel stop ok?



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Offline brodsord

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Re: Gear changing
« Reply #6 on: February 29, 2020, 05:03:14 PM »
Ahh.

Rear stand arriving next week from America.
I will try that as soon as it’s fitted John


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Offline K2-K6

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Re: Gear changing
« Reply #7 on: February 29, 2020, 07:03:01 PM »
When you put the drive chain on and the rear wheel is stationary,  then half the gearbox (the half connected to output sprocket)  becomes stationary too.  This generally makes it feel very obstructive so you shouldn't force it. Before that,  no chain, all the gearbox components can revolve together and in effect simulate the bike going along normally.

As John's advice above,  get rear wheel off the ground and try then,  it'll probably feel ok.

I wouldn't force it as described for risk of bending a selector fork.

Offline brodsord

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Re: Gear changing
« Reply #8 on: February 29, 2020, 07:10:25 PM »
Thanks K2.
I’ll get back to you both once I’ve got her on the stand.
Thank you both for your advice.


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Offline brodsord

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Re: Gear changing
« Reply #9 on: April 04, 2020, 02:50:03 PM »
Hi John, hi K2,

Seems I can move through the gears ok,
I can’t seem to get her to go into neutral,
I’ve just rode her around my drive and same thing, changes gear ok but trying to get into neutral is very difficult.
Thanks for any advice.
Graham 


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Offline Bryanj

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Re: Gear changing
« Reply #10 on: April 04, 2020, 04:22:11 PM »
Fairly normal, get used to finding neutral in the last few yards of rolling.

Offline brodsord

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Re: Gear changing
« Reply #11 on: April 04, 2020, 04:26:53 PM »
Thanks BryanJ.
It seems that is the norm,
I can cope with that.
Thanks for your reply


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Offline Spitfire

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Re: Gear changing
« Reply #12 on: April 04, 2020, 04:44:00 PM »
Yes as Bryan says as I approach a junction or traffic lights I get mine in neutral prior to stopping, or stop turn off and find neutral and start up again.

Cheers

Dennis
1976 CB750F

1977 CB750F2 In bits

1964 BSA A65R In bits

2000 NT650V DEAUVILLE

Offline brodsord

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Re: Gear changing
« Reply #13 on: April 04, 2020, 04:55:02 PM »
Thanks Dennis,
Did I read something posted from regarding this issue?


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Offline brodsord

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Re: Gear changing
« Reply #14 on: April 04, 2020, 04:55:36 PM »
Posted from you*


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