Clutch sticking in gear with Barnett coil spring conversion

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1200fan

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Hi all
My V-Max has always had problems with the gears sticking when I downshift - the gear lever won't go to the next gear down unless I blip the throttle first.
It also can't find neutral with the engine running, again I'd need to blip the throttle first before it does go in neutral.
Also when cold it clunks very heavily going into first and the bike wants to go forward even with the clutch in.
From looking into this I reckoned new clutch friction plates and steels were needed, so got them, took clutch cover off and found a Barnett conversion there instead!
Happy days! But need to ask if anything about this could be the cause of the shifting problems?
I took the plate off and the bolts were VERY tight, definitely more than the 5.8lb torque they're supposed to be. Could this be a cause.
I measured one of the Barnett friction plates and it was fine, but there are no 1 slot/2 slot cutouts on them so show which way they fit into the clutch. Is there a way to find how they fit in correctly?
Thanks all and apologies for the long ramble lol
 

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From what you describe it sounds like the clutch is dragging.
This is from the Barnett clutch installation guide. Note what is says in #4 regarding stack height. I would check that first.
 
The oil you use can also have an effect on the clutch. What's in-there?

It's years since I ran a Barnett clutch, and then it was just the friction discs, and not their additional replacement pressure plate. I used to have to hold the front brake on each morning, and when I toed it into 1st, the bike would lurch forward, and the plates would break free. After that, it normally would behave for the rest of the day, if I was starting it, and engaging 1st.
 
Cheers for your replies MM and FM, it's much appreciated.
Max Midnight, thanks for finding that, I'd been trying to look for Barnett fitting instructions. I've got the plates out now so I'll find out the overall stack height.
Fire Medic, I have Silkolene semi synth 10w40 in there at the moment. I have same thing with my bike, when cold and engaging first the bike jumps forward. So it may be a Barnett trait then, and something I'd need to do whenever I get on the bike. I'd also read on here somewhere about putting it in 2nd or 3rd, and rocking the bike forward and back against the gear to shock the plates free.
I saw when taking the plates out that there's no retaining wire or half size disc, so looks like the DD mod has been done too.
 
Cheers for your replies MM and FM, it's much appreciated.
Max Midnight, thanks for finding that, I'd been trying to look for Barnett fitting instructions. I've got the plates out now so I'll find out the overall stack height.
Fire Medic, I have Silkolene semi synth 10w40 in there at the moment. I have same thing with my bike, when cold and engaging first the bike jumps forward. So it may be a Barnett trait then, and something I'd need to do whenever I get on the bike. I'd also read on here somewhere about putting it in 2nd or 3rd, and rocking the bike forward and back against the gear to shock the plates free.
I saw when taking the plates out that there's no retaining wire or half size disc, so looks like the DD mod has been done too.

Do you have a Barnett clutch pressure plate, with six individual coil springs? They you do not have a 'double-disc' mod. The replacement of the innermost half-width friction disc with one of full-width is the 'extra plate' mod.

The addition of a used OEM diaphragm spring, sandwiched with the OEM diaphragm spring, is the 'double-disc' modification.

Because of the needless task of having-to free the sticky Barnett friction discs from the 'steelies' every morning is reason-enough to not use the Barnett friction discs, for me. The OEM friction discs give good service, assuming you don't abuse them.

As to the 'double-disc' mod, if you're running a big-inch engine, or with power adders, you might find justification for the 'double-disc.' Otherwise, to ease the strain on your hand, and to get increased clamping power, I prefer the PCW heavy-duty diaphragm spring.
 
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...I have same thing with my bike, when cold and engaging first the bike jumps forward. So it may be a Barnett trait then, and something I'd need to do whenever I get on the bike.
I saw when taking the plates out that there's no retaining wire or half size disc, so looks like the DD mod has been done too.

I think you will find that this is something that is not uncommon with a wet clutch particularly if they have stood for a while.
Pretty much every bike I've had did it to a greater of lesser extent.

Assuming the friction plates are in good condition then IMO replacing the half plate with a standard tune motor does not have any benefit.
If the clutch is slipping then that is the bikes way of telling you that the plates probably need replacing.
In addition, the gear change will be more 'clonky' as the spring washer that acts as a shock absorber has also been removed.

I think you will find that the DD mod refers to fitting a second diaphragm spring rather than swapping the half plate for a full one.
 
Thanks again FM and MM for your replies and my apologies for the mix up, I should've said the extra plate mod instead of the DD mod.
I've read elsewhere about the spring washer reducing the clunkiness. What came out the bike was 8 full friction discs and 7 steels.

Apologies again but I after some extra advice too...
Looking at the locknut on the clutch basket the tabs to secure the locknut are not in the right place so would that mean having to loosen/retighten the locknut?
Also in the other pic I've arrowed a gap that's showing between the locknut and central rod, is this how it should be?

Thanks again for your help again gents.
 

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Ok thanks FM, so I'll need to adjust the locknut. I don't have the clutch tool to hold the basket, so would it be safe getting the bike to 5th without the plates inside and standing on the rear brake to tighten it?
Thanks again.
 
Years ago, I bought the Motion Pro tool with 90 degree bend jaws, it's like a Vise Grip. I've also just used a long screwdriver across the clutch basket slots on opposite sides, but beware this can cause you to break the clutch basket sides! Not the best-way.

I think what you propose should work, as the primary gear from the crankshaft drives the clutch basket matching primary gear, then feeding through the gearbox to the final drive. As-long as it's in gear, that should work.

If you have an air impact, that could also break it free, or even a hand-impact tool and a BFH or a baby sledge.

In the pic it's hard to see, is one side of the locking tab flat against the nut, for nearly its entire length? And the other side is mostly on the one flat? You may be able to just bend the other side up to engage that flat for most of its length and not-worry about the 'overhang.' You want the malleable tabs of the locking washer to be tight to the flats, on opposite sides. A 'hex' nut should have 60 degrees for each flat on the circumference. I think the most-important thing is that the nut is torqued to-spec, which is usually a 'dry' setting (no oil or anti-seize) unless explicitly-specified otherwise in the manufacturer's assembly instructions.

I am not a pro mechanic, so if someone has a difference of opinion, have at-it.
 
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Many thanks again for your time and replies FM.

I've been looking into this again and now I think the tabs are OK. I've looked at the Haynes manual for the bike and found pictures of the locknut in place and the washer tabs are in the same position.

I've attached a pic of the locknut on my bike, the left tab is fully on one of the flats, and the right tab is halfway between, with one of the flat corners touching the tab halfway.

The Haynes pics are showing the locknut washer fitted on its own which shows the angle of the tabs, and with the locknut fitted, and they're showing in the same place as I have already.

So it looks like the locknut and tab was in the correct place anyway. So I just need to clean the discs up, put back in and see how the bike behaves now.

My apologies again for getting it wrong on this but hope this helps someone in the future.

Thanks again FM for your fantastic help on this.
 

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you have one tab bent up against the nut already, there are 2 tabs at different angles so that one of them should align with a flat on the nut
 

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