Longer swingarm

[donkeychomp]

Is there one that will fit an LC without too much bother? I think they look better a little bit 'stretched' . This is on a bike running the standard rear wheel and drum brake...

Alex

[jon]

At the risk of being acussed of being a heretic, I completely agree. Sure an RGV arm looks a little too long, which is offset IMO by the improved look of wider wheels.

There are arms in between. I used a modified TZR 2MA arm, and it’s somewhere in between. It may be too much of a departure from the LC look for you though.

I did think about building a period looking arm from steel box section similar to a Davida longer than an LC arm, but in the end went for matching TZR front and rear. A bit old school hybrid from the 90’s.

The rear light sticking out so far egsagerates the wheel being so far forward. In fact in some shots an LC looks like it’s been shunted from the rear.

Jon

[donkeychomp]

Interesting Jon. I have a 2MA so I could try a swap. Do you have any pics of the mods you had to do?

Alex

[headcoats]

In fact in some shots an LC looks like it’s been shunted from the rear.

That's how I see it too

Don't like standard LC's though, but don't like over the top ones either !
each to their own

[alext]

This interests me too.

I have FZR400 wheels on mine - the 18" rear wheel is in the standard LC arm, spread apart till it fitted.

it looks far too short - another inch or so would make all the difference and not screw up the handling too much.

I was looking at modifying a YPVS arm - its longer but not wide enough for me, I was thinking serious surgery is required - probably fabricate new arms onto the YPVS pivot.

unfortunately there was no way the FZR400 3TJ rear wheel would fit in the LC arm - it was far too wide to even go in the suspension loop.

[donkeychomp]

I've tried an FZR400 wheel. It fits with widening but looks wrong. I thought about welding some 'extension' bars on but I don't think an LC swinger will take it!

Alex

[dusty350]

Hi mate,
I agree - welding extensions onto the end of the Lc swingarm probably isn't a good idea. Apart from the safety aspect, I think you could mess up the handling in a major way and put a lot more stress through the rear end. I know the "technology" around 80's era bikes seem primitive compared to modern bikes, but a lot of what Yamaha did back then was based on sound experience from years of racing. That's not to say we cant improve things with modern tyres/wheels/forks/brakes/swingarms and shocks of course !! If you are keen to mod the original Lc arm, rather than just extend the back of it, have a look at this link from the 2stroke forum. Tony is a member on here - hope he doesn't mind me linking his build thread - and he did wonders with an Lc arm, which is food for thought

2strokeforum.com/thread/11804/lc-350-hybrid

Dusty

[jon]

Mar 30, 2018 8:25:50 GMT 1 dusty350 said:

Hi mate,
I agree - welding extensions onto the end of the Lc swingarm probably isn't a good idea. Apart from the safety aspect, I think you could mess up the handling in a major way and put a lot more stress through the rear end. I know the "technology" around 80's era bikes seem primitive compared to modern bikes, but a lot of what Yamaha did back then was based on sound experience from years of racing. That's not to say we cant improve things with modern tyres/wheels/forks/brakes/swingarms and shocks of course !! If you are keen to mod the original Lc arm, rather than just extend the back of it, have a look at this link from the 2stroke forum. Tony is a member on here - hope he doesn't mind me linking his build thread - and he did wonders with an Lc arm, which is food for thought

2strokeforum.com/thread/11804/lc-350-hybrid

Dusty

Dusty, I’d like to say respectfully that I don’t agree with your comments entirely for two reasons:

Firstly, sure a couple of bits of steel tack welded to the end to extend it is probably a bad idea. However think about how an LC arm is constructed. It is welded together. I would think that if the adjuster plates were made longer, the old ones removed and the new seam welded in that should be fine?

Secondly, I see where you coming from with the longer arm putting more stress through the frame, but what about RGV arm for instance? These are much longer than an LC, and yet many have them fitted including yourself.

At the end of the day it’s down to the individual being comfortable in the safety of their own bike. I don’t like the idea that some people do of using aluminium bolts to hold disks on but people do it without issue (as far as I’m aware).

Just my opinion, I don’t want to seem confrontational and considered not replying, but wanted to voice my views.

On the subject of FZR wheels, the wider 17” x 4.5” wheels will be touching on chain run in a standard LC frame. I’ve had to widen my LC frame to accommodate this wheel.

Jon

[dusty350]

Hi Jon
We don't all have to agree - I have no problem with differences of opinions - it's a forum after all. The link I added shows a way to mod an Lc arm which I think is a more appropriate way of doing it. Adding extensions onto an Lc arm just seems a dodgy way to do it to me, but you are the engineer and I'm not so maybe extending the original arm is ok. And I'm not saying a longer arm would stress the frame - just extensions may stress the Lc arm. The way you say of doing it makes sense, but that's not what I imagined Alex meant - we all imagine things differently of course. Each to their own of course, but if I was extending the Lc arm I would do it differently to just adding bits on the back.
And both my swingarms are Metmachex - I don't have Rgv arms in mine

Regards

Dusty

[jon]

Hi Dusty,

I’m not saying it’s the best way to do it, but IMO it wouldn’t be dangerous. Those adjuster plates are quite thick, and if you were worried you could go up a millimetre or so for rigidity.

I wasn’t referring to your latest 2 hybrids, but didn’t the hybrid you sold dono have an RGV arm? or are they grey cells failing?

I think the most stress in a longer swingarm for most of a road going bike (upright) would be the greater leverage on the shock, transfered to the frame.

Jon

[dusty350]

Hi,
Don't worry Jon, your brain cells are intact !! I've had 2 bikes with VJ22 arms fitted. My blue - now orange hybrid came with one already fitted. I had always wanted an ally Metmachex, so sold the VJ22 arm which part funded the Met. My white hybrid came with a new Met already fitted. The bike I sold Dono came to me with a Vj22 arm fitted. As much a I wanted a third hybrid, I decided to sell it on to fund finishing the other 2. I don't mind the Rgv arms in an Lc, but I think if they were 2 inches shorter I think they would look better. As standard I believe they are approx. 4 inches longer than an Lc arm overall. It's a great shame there aren't more firms producing swingarms for our bikes. When you think there are probably 10+ different makes of pipes available now, but only really Metmachex that make bespoke swingarms. When you think back, there was Davida, Micron, JMC and Dresda making arms for all sorts of bikes to name a few. I did have a box section arm last year - bought off ebay, and I cant remember what make it was, but I've seen a few so it wasn't a one off;

20160727_140542 by David Miller, on Flickr

Not the prettiest of swingarms but longer than standard and certainly stronger;

20160727_134550 by David Miller, on Flickr

I also had a fairly rare Hejira, Lc arm, fitted to my 400 mono a few years back. I was told they were made for racing. Box section steel, it was very strong but I never compared it's length to a standard Lc arm so cant say if it was longer or not;

Rd250 mono project 010 (1) by David Miller, on Flickr

Dusty

[earthman]

Weren't the LC swingarm designed to be short on purpose?   

[donkeychomp]

Hmm thought I replied to this! Apparently not...after reading everyone's ideas I think I'll find another LC swingarm (mine isn't the best out there) and get it lengthened by about 50mm. Would BSB in Staines do that Dusty?

Thanks everyone for the input, most appreciated.

Alex

[tell7437]

Dusty I think that box section arm you had belongs to me now, bought it off muttsnuts last year.
No idea what make it is but I like it & the length looks just right.

Trevor

[dusty350]

Hi Trevor
Yea, Mutts had it off me, so the same arm. I do know the name of it - just got to remember, or find the post where I mention the name !! I will let you know when I do. I've definitely seen a few the same so it wasn't a one off.
Alex, BWB would be able to do it I'm sure. Clive is the fella you need to speak too, and he's a biker himself. Just depends how busy they are as they are doing a lot of film stuff for Shepperton at the mo. Have you got their number ?

Dusty

[donkeychomp]

No I don't Dusty could you text me it please.

Alex

[oldelsieboy]

Mar 30, 2018 20:55:35 GMT 1 donkeychomp said:

Hmm thought I replied to this! Apparently not...after reading everyone's ideas I think I'll find another LC swingarm (mine isn't the best out there) and get it lengthened by about 50mm. Would BSB in Staines do that Dusty?

Thanks everyone for the input, most appreciated.

Alex

You did reply, just in the wrong thread.

rdlccrazy.proboards.com/thread/43455/building-lc-parts?page=2

OEB

[jon]

Mar 30, 2018 20:55:35 GMT 1 donkeychomp said:

Hmm thought I replied to this! Apparently not...after reading everyone's ideas I think I'll find another LC swingarm (mine isn't the best out there) and get it lengthened by about 50mm. Would BSB in Staines do that Dusty?

Thanks everyone for the input, most appreciated.

Alex

Hi donkeychomp, I’ve got a good condition LC arm I’d sell for £50 plus postage. If your interested I could post photos, let me know.

Jon

[howard]

Some of the aftermarket arms like my JMC had slotted or drag style adjusters too.

[midlifecrisisrd]

Metmachex also offer a longer slotted option

Steve

[oldelsieboy]

Mar 31, 2018 10:28:45 GMT 1 midlifecrisisrd said:

Metmachex also offer a longer slotted option

Steve

A couple of years ago I enquired about such an item & was quoted a price of £780

OEB

[dusty350]

Every "option" on a Metmachex arm costs extra
When I ordered mine I enquired about the normal type of chain adjusters and they were £60 extra, chain guard £25 extra, nylon chain protector was extra etc etc. If I was ordering another I would avoid the eccentric chain adjusters. They are not as accurate as you would imagine and alter ride height every time you adjust the chain.

Dusty

[howard]

There's one on eBay now , the seller is a regular on here might be worth a punt.

[donkeychomp]

I will go looksie, ta for the tip.

Alex

[dusty350]

Tell7437, Here is another like yours;

www.ebay.co.uk/itm/yamaha-rd350lc-rd250lc-swingarm-box-section-in-steel-swing-arm/273137749877?hash=item3f98474f75:g:MgcAAOSw~xVawPwl

I paid £160 for the one you have that was in great condition, so this seems overpriced

Dusty

[dbgr]

Yea, its got one of those really hard to find spindles..

[earthman]

Apr 1, 2018 20:05:53 GMT 1 dusty350 said:

Tell7437, Here is another like yours;

www.ebay.co.uk/itm/yamaha-rd350lc-rd250lc-swingarm-box-section-in-steel-swing-arm/273137749877?hash=item3f98474f75:g:MgcAAOSw~xVawPwl

I paid £160 for the one you have that was in great condition, so this seems overpriced

Dusty

To be fair, every LC item he puts on ebay is overpriced.

[dbgr]

Hey Dusty how long ago was it you owned that Hejira swinging arm I seem to remember they had tuning parts available for Honda and Yamaha race bikes when the late great Phil Mellor was racing Honda 125s many moons ago now, they were even sought after then...

[dusty350]

Hi
It was a good 10 years ago, maybe 11. I bought an aircooled rolling chassis off a fella on the aircooled forum. E frame, Rzr forks and wheels and yokes and the Hejira arm. It was only when I virtually finished the project, someone on the forum identified the arm as a Hejira item, reputedly made for racing on the IOM, although I cant confirm that. It was nice but I didn't think it was that special at the time ! It was steel so not particularly light, but certainly stronger than a bendy Lc arm !!

Dusty

[dbgr]

Hi dusty, I seem to remember through the foggy mists of time that it was affiliated to the Honda Racing Corporation at the time so was very important to Honda..