Metchamex swingarm

[sheep911uk]

I’ve got an original metchamex swing arm and I’m in two minds whether to sell it or fit it.
Are there any benefits from fitting it and are there any downsides?

[jessy03]

Probably just looks, I’ve a standard one to px if you decide to sell it on 👍

[dougw]

I`ve never quite bought in to the "Standard 350LC swingarms are really flimsy" theory, they seem pretty stiff to me.

The standard swingarm bushes do leave a lot to be desired though, and the standard rear shock lack of damping probably contributed more to the "Yo-Yo" like weave you got when racing them on oversize race tyres than chassis stiffness, imho .

I have a JMC arm in my 4L0, and with its taper roller bearing set up removing the rigidly clamped tube of the stock arm I think its probably removed some overall stiffness from the chassis.

It does look pretty though.

[dusty350]

I've had a few now - I like to build a bike with a Metmachex fitted if I can. Always wanted them way back but could never afford one back then.
I have an original on the 250 I'm currently building. Certainly didn't flex as much as the standard tubular arm when I tried them both. They do look trick too, I think.
The bit I'm not keen on is the eccentric adjusters - a big selling point in the day but actually not that accurate in real life. Even on a brand new arm with eccentrics. I tend to get straight pull adjuster arms if buying new now. The other thing with the eccentrics is when you adjust them for the chain tension, you alter the ride height. Not the end of the world but if you have the bike set just right, and then adjust your chain, the ride height will alter.
Spares are no longer supported by Metmachex for the originals, but bearings should be generic from a good bearings place, but if you need the 3 spacers you will be getting them made bespoke. Mine was missing one of the short spacers that sits in the bearing, and I had to get it copied from the one that I did have - still worth doing in my opinion though.
Personally I would use it if you have it, but even an original in good nic fetch a good few quid should you move it on

[reedpete]

If the box section aluminium design and construction is what they put on the TZs, then it will do for an LC !

[veg]

Tz swinging arms do have more bracing though than either a standard arm or even the metmachex and imo look far more impressive. I’ve contacted Tamsin to see if they will do a one off arm combining the tz bracing with Lc fitment but unfortunately they are too busy doing standard arm so won’t do it.
I’m with Dusty on the later arms and the non eccentric adjustment, Ive an original metmachex and would prefer the non eccentric adjuster but I’ll live with what I have.
TBH if you are at the point that you are thinking about chassis flex you’d be better bracing the original frame as per JonW. The first point being the swinging arm mount on the frame. You have a small spindle size in a single plate mounting. You are talking about 1970/80s chassis design. You also need to account for if you change one part then you need consistent changes otherwise you’ll just highlight another area for change.
For me the standard chassis is good enough for what it is. If however I was going for big brakes big suspension big bore motor I’d agree you need to make significant chassis changes.

[sheep911uk]

Thanks for the replies, my decision will be purely on cosmetics, it came on a project bike so I’m considering using it.
What’s the value if I decide to sell, it’s currently away being polished.

[veg]

Value is guess at around £4-450 new they are what £600 ish? Dusty will know new price I’d imagine as he has single handled kept them in business. I like the look some don’t it’s pure personal choice. That’s if it is all complete. You need to ensure you’ve all the correct fittings esp rear wheel spindle I bought one of the last spindles available cost me £110 then I found my original one.

[veg]

The other consideration is make sure you fit a chain guide on the top of the arm near the swinging arm pivot point as the chain can wear the alloy. I and I believe Dusty have used hard nylon so it gets worn if the chain is either loose or flaps.
Also be mindful of the eccentric position as it changes ride height depending if it’s at the top or bottom position.

[dusty350]

Hard to price an original. Depends on condition, like every used part, but I guess 250 -300, maybe a bit more ? Can't remember the last one I saw for sale, as I never look for them, so I don't know how rare, or not, they are.
And Veg is right regards a chain slipper. I use nylon chopping board from the Pound shop. Ideally drill and rivnut the arm to bolt it on properly. A standard rubber guide from an Lc arm won't fit I'm afraid.
I would always choose one over a standard arm, but selling it will release funds if you are tight for cash😉

[beardy]

My chain guide solution

[markrd250lc]

I just brought a new one , i think it was around £800 with chain protector and paddock bobbins, then ordered a alloy brake bar from NK racing, i just love the look of them.

Mark

[dusty350]

Was £800 for a standard Lc wheel ?

[markrd250lc]

yes it was , i will check the price, it was before Christmas

[avb]

I really like heres the 3rdone I've bought going on my new project at the weekend

[markrd250lc]

It was £620 (eccentric), Chain guard protector £19, Paddock bobbins £12.40 ,,£779 total inc vat and P&P

[sheep911uk]

Feb 7, 2024 20:47:50 GMT 1 markrd250lc said:

It was £620 (eccentric), Chain guard protector £19, Paddock bobbins £12.40 ,,£779 total inc vat and P&P

Hi Mark will the chain protector fit the original ones?

[markrd250lc]

not sure tbh , mine looks like its screwed on, i think Dusty would know, the last Metchamex i had was 1990, i think there's a thread on here where some people have made their own.

Mark

[sheep911uk]

Feb 7, 2024 22:49:29 GMT 1 markrd250lc said:

not sure tbh , mine looks like its screwed on, i think Dusty would know, the last Metchamex i had was 1990, i think there's a thread on here where some people have made their own.

Mark

Thanks mark, I think I have an old one off my ktm Enduro I will see if I can modify that.

[veg]

Easiest thing to do drill fit a captive nut fit the chain guide. Nylon is the best.

[sheep911uk]

Feb 8, 2024 16:27:38 GMT 1 veg said:

Easiest thing to do drill fit a captive nut fit the chain guide. Nylon is the best.

Thanks I’ve got some Rivnuts

[stusco]

I made mine from very hard nylon and stuck it on with industrial double sided tape its never budged in ten years

[sheep911uk]

It’s just back from being polished and looks fantastic !!!

[sheep911uk]

Can I use the centrestand with the metchamex fitted?

[dusty350]

Yes, no reason why not🙂

🙂

[reedpete]

Feb 10, 2024 18:48:40 GMT 1 dusty350 said:

Yes, no reason why not🙂

🙂

Didn’t know you were still issuing permits ! 😂