Girders

[hornet6]

Those look sweet.Are they brazed at the headstock.....it looks well sorted.

[tbone]

Not sure, but TB's made scaled down models of parts before -are these full size or miniature?
Taz's trike build uses chunky girders, built for us by FLC, (Mick), from Yorkshire. I'm looking forward to trying them out. 

  these are full size  , 33 inches from the top yoke mount to the wheel spindle mount.
As for material ect, I did say at the start of this thread that i would not be going into great detail and thats purely beacause every application should be looked at on an individual basis.....as a general rule though (and only because you pushed me  ), for a `standard` set of girders going onto an `average bike/trike,` i would use 1" OD tube with a wall of 3.5mm ish. Need not be special tube, same stuff we build frames with is fine but (aint there always a but...) you will need to fit bushes into the links so seamless will save you the work of grinding the internal seam away.

Personaly i have to agree with Dracken on the handling, Girders are regarded as an old fashioned front end, couple that with poor quaility as an attempt was made to mass produce them and they are percieved as the third choice for bikes which is fine because they way we handle a bike is very different to the way we handle a trike. Having said that, unless you want to tear around at 150mph everywhere, girders will still out perform forks in looks, suspension and steering. 

[morrag]

Draken, the girder forks you display, are, I take it, a set of your own manufacture, and like the frames you have shown us in the past, appear to be of the same very high standard of construction. You bullet points I cannot disagree with, but must point out that the style of engineering shown comes at a fairly high price! one which many would not be in the market for, and therefore the ubiquitous 'tele' fork becomes a cost effective, mainstream, alternative. I am so old that I started my motorcycling career on girder forked machines, usually with worn out bushes and swaged pins! so their frailties have probably coloured my opinion! and well remember the revelation regards handling that the first pair of ex-W.D Matchless teles.were!Modern spring/damper units are definite improvements over the simple open springs and friction dampers of my youth! so, if you have the wedge, and want to be 'different', then modern girders it is. Alternatively, if you want cheap, serviceable and simple.......you know what I mean, still 'yer pays yer money....' , but better, I think not!TTFN, Morrag

[panthershaun]

You have very obviously never ridden a machine equiped with old style 'Girders', but the answer is NO.......unless you have some kind of death wish. They are ok for 'Show' but don't even come close to a modern, telescopic,fork,in performance. I am of course excluding the modern, 'Beamer versions of the type!which I have never tried, Morrag

yep I have ridden several and have had no issues with the handling to date, a couple had worn girders and they were awful but once revamped again no problems. I'm talking old 30's-40's bikes, rigid framed old chuffers that are never going to be racers 

[morrag]

Well,on old machinery from the period when girders were the norm, they are just about passible when in tip top order, however, my warning was to Hornet after his query re" powering out of long bends that you had been cranked over on!", yeah, right, there you go then, I'll go with teles. or even Earles type if its a trike, in those situations, thank you!...Morrag

[pastyman]

did these girders ever get finished, if so is there any more piccies please

[tbone]

oh....erm..... no. When i started these i had an idea of what i was going to fit them onto, but i didn`t actualy have the frame which made fabricating the yokes impossible.

[pastyman]

lol no worries 

[tbone]

Byzmax is the man you need if its girders your after, he`s done at least 3 sets recently 

[hornet6]

Hi.Just thought i would pick up this thread again. Ime still considering building my own girder forks for my next project.Ive been looking at the durfee girders which i can imagine, will be expensive.In their write up,they use chrome moly tube for its strength and lightness.Does anyone know how much it costs per metre,or is it safe enough to go with seamless mild steel.
My idea is to get all the parts machined and scalloped,and then i will make a jig to hold everything tight together while i weld it.I want to keep the rake at about 32 to 34 degrees.
Also,what type of shock absorber do i use? I was thinking of using a rear shock so that i could make adjustments between soft and firmer settings.Any thoughts greatly received.     

[voodoo]

HHMMM got to admit my old Zed chop handled well enough and trust me that thing got hammered lol...Voodoo....

[hornet6]

I like the set-up.Thats sort of what i want to make....but not as long.Did you make them yourself,and if so what material and size did you use?

[voodoo]

Nope not something I would be confident enough to try and make myself....those things are about 20 years old now...Voodoo...

[tbone]

I`d be happy to go with mild steel tube, you only need seamless for the pivots.
cant help on the shocker, will be using a single spring on mine, when i get round to looking at them again.
Byzmax is still the man to ask about girders, drop him a pm and i`m sure he`ll pick it up next time he`s in.

[ByzMax]

Girders are fantastic things.

However no amount of clamping will stop them distorting. It's about welding process and doin stuff in the right order that ensures they come out straight. There was a brilliant website explaining the pro's and con's but it's of line at the moment. I'll try and post up some more thoughts on sunday perhaps when I have more time.

There are a set for sale on Britchopper never been used and at price you'd struggle to make em for.  £350!!

Click the link.  http://www.britchopper.co.uk/forum/viewtopic.php?f=41&t=27850

Think he is a member here... Maybe?

Any how suspension set up is trial and error. I usually fit any old rear shock and then guage from that what's actually required.

Standard steel frame tube (cds, cfs) In years gone by they where made from solid bar! You can Mig weld them but remember that the welds are generally short and you would do well to preheat the parts to ensure good penetration. Tig welding is better and if you can do it makes for a better finish. Accuracy of the finished parts is everthing.

There are lots of issues when building them much of which is related to getting the trail correct as they are generally built to order