Author Topic: 4th Gear noisy  (Read 217 times)

Offline MarcoM

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4th Gear noisy
« on: September 12, 2020, 12:35:32 PM »
Hi All,

Since a few weeks I'm the happy owner of a CB500K1. It runs great and and the gearbox seems to work fine but... when I use the 4th gear I hear a ticking/knocking noise. It only happens in 4th gear and there ar no shifting problems.
Any ideas what this could be?

Thanks, Marco

Offline K2-K6

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Re: 4th Gear noisy
« Reply #1 on: September 12, 2020, 03:35:24 PM »
Welcome to the forum Marco.

Those type of noises in a gearbox always make me nervous as they can be potentially serious. Generally with the gear shafts running on the same bearings for all gears it's less likely to be caused by those.

One of the areas of vulnerability in these boxes I believe is bent selector forks,  that my be trying to engage more than one gear simultaneously with attendant noise to indicate that one component is rattling against another.

Not sure if there's any way to easily check for the above,  but maybe removing the clutch and putting it in 4th gear to rotate the geabox via the rear wheel and see if there's any obvious "snatching " on the gearbox shaft.

Someone with more intricate knowledge of the 500 than me will likely be along soon to offer their view.

Offline MarcoM

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Re: 4th Gear noisy
« Reply #2 on: September 12, 2020, 05:45:57 PM »
Thanks for your reaction, these noises always make me nervous too.

Offline OZZYSBIKES

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Re: 4th Gear noisy
« Reply #3 on: September 14, 2020, 11:56:45 AM »
Don't want to be a scaremonger but....
If you've ever had a gearbox seize while riding a bike you don't take any chances,

I had just returned from a high speed run on a kettle when the gearbox seized doing 30mph, I managed to stop the bike without crashing and thanked whoever is looking after me,

That was due to worn bushings inside the gears, two gears jammed,

I would be stripping it

Sorry to be negative but I think I was very lucky,  ten minutes earlier doing over 100mph it could have been very nasty

Offline K2-K6

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Re: 4th Gear noisy
« Reply #4 on: September 14, 2020, 01:54:58 PM »
Don't want to be a scaremonger but....
If you've ever had a gearbox seize while riding a bike you don't take any chances,

I had just returned from a high speed run on a kettle when the gearbox seized doing 30mph, I managed to stop the bike without crashing and thanked whoever is looking after me,

That was due to worn bushings inside the gears, two gears jammed,

I would be stripping it

Sorry to be negative but I think I was very lucky,  ten minutes earlier doing over 100mph it could have been very nasty

I don't feel you're being negative,  it's as you say and pretty serious if it locks.  Unlike an engine seizure,  pulling the clutch does nothing to help with the rear wheel effectively locked if the box is badly compromised.

Certainly needs conclusive investigation to ascertain true cause,  whatever that may be.

It's the history of bent forks that's been discussed on forum before that raises my initial suspicion.

 

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