Author Topic: First Gear Crunch  (Read 4421 times)

Offline bucksfizz

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Re: First Gear Crunch
« Reply #15 on: October 18, 2019, 06:18:55 PM »
I finally got round to removing the clutch.
Talk about a pain trying to remove the castellated nut securing the clutch basket.
Even with the correct tool and locking the clutch with the bike in 1st gear and the rear brake on, the nut refused to budge.
The problem was that I couldn't get enough purchase on the nut and hold the rear brake pedal down at the same time.
In the end, I locked the clutch with Mole grips/channel lock pliers butting up against a length of wood:

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The clutch plates were reasonably clean, but I cleaned them with petrol nonetheless.
With fresh oil in the oil tank, I fired her up, and selected 1st gear...
Hurrah! A noiseless gear selection - as I thought, it was clutch drag.
I'm just hoping the noisy gear selection won't return.
If it does, I'll try the clutch basket modification.

Offline Nurse Julie

  • 1977 CB550/4 Mongrel Brat. 1974 UK 500/4 K1. Honda CD250u.
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Re: First Gear Crunch
« Reply #16 on: October 18, 2019, 07:25:30 PM »
We'll done 👍👍👍
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https://www.ebay.co.uk/sch/julies9731/m.html?item=165142672569&rt=nc&_trksid=p2047675.m3561.l2562

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http://www.sohc.co.uk/index.php/topic,14049.msg112691/topicseen.html#new

Offline MarkCR750

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Re: First Gear Crunch
« Reply #17 on: October 18, 2019, 09:06:03 PM »
I did the clutch mod on mine, it still clunks into first, I’ve never seen one that doesn’t, it’s about 3 years ago that I did the mod but I seem to remember it was an improvement, if you really want to avoid the crunch buy a Carby 900ss, proper dry clutch set up on that , I can’t even tell it’s gone into first sometimes!
« Last Edit: October 18, 2019, 09:31:58 PM by MarkCR750 »
Suzuki GT250A (Nostalgia)
1977 K7 CR750 (lookalike, what of I’m not sure)
Ducati 900SS (Soul & Speed)
Ducati M900 Monster (Handling & character)
Thruxton 1200 (suits me)
James Captain 197 (pure adrenaline, i.e. no brakes!)
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Offline Green1

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Re: First Gear Crunch
« Reply #18 on: October 19, 2019, 09:46:50 AM »
Both my Hondas and Kawasaki's go crunch but my Guzzi goes with a BANG
They all make a lovely noise when you put them in gear while still reving a bit high on the choke  ;D
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Offline Trigger

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Re: First Gear Crunch
« Reply #19 on: October 19, 2019, 02:39:00 PM »
I did the clutch mod on mine, it still clunks into first, I’ve never seen one that doesn’t, it’s about 3 years ago that I did the mod but I seem to remember it was an improvement, if you really want to avoid the crunch buy a Carby 900ss, proper dry clutch set up on that , I can’t even tell it’s gone into first sometimes!

The clutch mod is only for the early clutches as, they did not have any drain holes.

Bucksfizz, that is the worst way to lock a clutch up. It is very easy the break the alloy parts, you can lock a clutch with only 4 washers  ;)

Offline bucksfizz

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Re: First Gear Crunch
« Reply #20 on: October 20, 2019, 02:44:06 PM »

The clutch mod is only for the early clutches as, they did not have any drain holes.

Bucksfizz, that is the worst way to lock a clutch up. It is very easy the break the alloy parts, you can lock a clutch with only 4 washers  ;)

OK, thanks for the tip - the K3 does have some drain holes.
Oops - it looks like I was lucky then, even though the clutch vane looked strong enough to take the mole grips.
Out of interest, how do you lock up the clutch with four washers? TIA

Offline Trigger

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Re: First Gear Crunch
« Reply #21 on: October 20, 2019, 02:53:11 PM »
Very easy, 4 washers under the bolts that will compress the springs and lock the clutch  ;)



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Offline bucksfizz

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Re: First Gear Crunch
« Reply #22 on: October 20, 2019, 04:19:01 PM »
Brilliant - it's easy when you know how.

Offline Seamus

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Re: First Gear Crunch
« Reply #23 on: November 10, 2019, 08:44:16 AM »
FWIW, old Brits used to crunch into 1st (Honda don't have the monopoly on this), usually after starting from cold. Kicking over with clutch held down freed the plates and helped. Don't know if this would help on a Honda, as mu old 750 used to do it.

Maybe selecting 2nd before 1st would help....

Offline MarkCR750

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Re: First Gear Crunch
« Reply #24 on: November 20, 2019, 09:58:13 PM »
Yes, same mod that I did, as above I think it made it better but it’s easy to kid yourself with such things, and it’s 3 years ago so I can’t remember how bad it was before, I think the “they all do that sir” is the best philosophy with Honda first gear selection.
Suzuki GT250A (Nostalgia)
1977 K7 CR750 (lookalike, what of I’m not sure)
Ducati 900SS (Soul & Speed)
Ducati M900 Monster (Handling & character)
Thruxton 1200 (suits me)
James Captain 197 (pure adrenaline, i.e. no brakes!)
"Eff yir gitten awvestear yir gooin te farst"
Sir J.Stewart.

Offline adespin

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Re: First Gear Crunch
« Reply #25 on: November 21, 2019, 12:15:10 AM »
My K1 has a horrendous crunch when engaging 1st gear on cold start up after no use of about a week, my solution to this is before starting the bike, i select 5th gear, pull the clutch lever in and rock the bike back and forth untill it frees, usually no more than one rocking, then engage 1st gear, kill switch to off and turn the engine over on the starter motor with the clutch in and brakes on,  and that does the trick, no need to do it again untill the next short lay up.
« Last Edit: November 21, 2019, 12:17:05 AM by adespin »
1971 cb750 K1

Offline MrDavo

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Re: First Gear Crunch
« Reply #26 on: November 25, 2019, 03:00:13 PM »
Clunk Click Every Trip, as someone who shall remain nameless used to say in an advert.

My CB750 had one finger clutch operation but still made a loud clank has going into first.

My Harley is worse, it sounds like one of those .22 shooting galleries you get at fairgrounds.
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Online K2-K6

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Re: First Gear Crunch
« Reply #27 on: November 25, 2019, 03:52:03 PM »
Clunk Click Every Trip, as someone who shall remain nameless used to say in an advert.

Now then, now then, now then,  jingle jangle  :D

Before starting,  and with both wheels on the ground,  put it in 1st gear,  hold front brake and kickstart to turn motor.  Should free any dragging clutch plates first,  then into neutral and fire it.

Most Japanese bikes drive the motor from the kickstart via primary drive so you can kickstart them in gear rather than through the gearbox.

 

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