CNC Swingarm 'Gull Arm' Whats your opinion?

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I_THUMP

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I first seen these cnc 'Gull Arm' swingarms on the Monstermoto bikes in the UK. The wierd look and design of them cought my eye and also Monstermoto are hard to miss on the UK Mini race scene. They have many wins in all forms of mini racing including mini sx Brittish champions. All of there riders have a choice of the 2 swingers but many choose to race with this Gull Arm style swinger coz they like the ride and handling of it.

Ive been wondering if this style swinger has any benefits or advantages over the standard style swinger on mini bikes. Im not just asking for your opinion on how it looks but im interested in your thoughts on how well u think the suspension would perform ect? Would it put the bike under any more or less stress or no difference?

The one negative I can see on that frame in the pic is that it has no cradel mount.

1183389885KXPP-104_edited.jpg


This is that frame and swinger on the bike
138-cc140cc-Air-Cooled-High-Quality.jpg


The MonsterMoto
MK2_right_side_moody.jpg


and I thought Id add this pic of the CNC Frame with the standed swinger (I luv that subframe)
1183389458KXPP-097_edited.jpg
 
where can i ge tthat last pic frame with the normal swingarm and how much???
 
I can tell u its not cheap and I dont think u will find it in Australia yet but I will let u know a price on it soon.
 
its about 550$....and the gullswingarm is decend for supermoto...stiff and light ...for mx you want to have a longer arm!!
 
in the last pic
i run that subframe and swingarm on my full alloy frame
 
it looks similar to the frame used on the 05 thumpstars. I would kill to get hold of one of them with the longer swingarm (not the gull arm one). Is there any way of ordering them in?
 
The gull swingarm lowers stress on the frame .... it's half way in between a straight swingarm and an "A" swinger . Since they have less leverage ... you don't need a 1000 lb shock .... you could use a BS22-AR type shock with a 350 to 550 lb spring ......

One of the main benefits of running that type of swinger is that chain rub and wear problems (plus noise) would be minimised or even eliminated ..... the chain only has to clear the pivot bolt and they probably have a roller for it to run on ........

Those alloy back bones are super strong .... especially if they're the rolled T-6 heat treated ones like the Thumpstars used to run which were made in Germany .....

You just have to get used to the weird look of the swingarm ..... but at the end of the day ...... function and reliability are far more important than looks ...... :)
 
One of the main benefits of running that type of swinger is that chain rub and wear problems (plus noise) would be minimised or even eliminated ..... the chain only has to clear the pivot bolt and they probably have a roller for it to run on ........

Those alloy back bones are super strong .... especially if they're the rolled T-6 heat treated ones like the Thumpstars used to run which were made in Germany .....
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well like you said ,but having no chain slider was one of the cruxes of that swingarm....mostly the chain got off ALL the time in dirt:p and for the making the part in GER....mmm...that would be interesting to know who??:p Das glaube ich nämlich nicht !!;) hahahahaha
 
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well its like this ...this very smart yellowman send a sample to one of this places and it will be certified ,that its aluminium and got the ability that a kid can ride with this frame without getting hurt...then they pay for that and receive some nice stickers from this company...thats all!!
This kind of certification you can find in germany on almost everything ...shampoo, toaster, chewing gum, etc.....it means practically nothing though !!
So, the frame is still chilumium, if a adult can use it up to the edge is still questionable and all of this is some advertisement move like OGM now says ,they are working with BBR....yeah right!!
 
That may well be mountain ... I don't know about the frame that I-Thump posted pics of but I have personally inspected genuine Thumpstar T-6 billet frames (the TUV certified solid billet spinal frames) and was quite impressed with them ...... the TUV certification was stamped into the frame ...... they most certainly definitely didn't look like they were made in China .... the spine part was one solid piece that was bent by high powered hydraulic roll forming machinery ..... the human riders bones would snap and crush long before those frame back bones ever bent ......

It doesn't matter where in the world things are made these days .... most of the parts are made by million dollar Computer Numerical Control Machinery .... the workers just handle and assemble the finished machined parts . Hi quality parts can be made anywhere ....
 
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atomik had the frame listed on ebay for $350 buy it now
and the swingarm for 90 buy it now earlier this week
 
Atomik are now selling these type frames and swingers.
$350 for the frame and $90 for the swinger

005E-Frame.jpg

005E-Swingarm.jpg
 
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You can easily tell the difference between the good strong alloy and the weaker crap .... the strong stuff has been made from either vacuum degassed die casting (looks really smooth and grey coloured , has die marks , and has higher density so is fairly heavy) OR high quality roll formed billet alloy meaning it was formed straight and has been forced into shape so it's also fairly heavy ..... anything like a frame that is made in one piece and machined will be junk because the grain structure doesn't flow in the same direction evenly along the length .... they can be made from a pour cast billet which is no better than a standard casting and is brittle .... to test it to see if it's junk , you only have to tap it and see if it dents or marks easily........

The genuine Thumpstar frames are such good quality that they have already been put thru the test when they are bent during manufacture ..... for a start a good frame won't be coated with that silver frost paint looking crap ... That's done to hide the bare alloy from those who know good quality alloy when they see it .... and also to hide linishing and sanding marks where they've removed casting flash ......

The Thumpstar frames are bare untouched alloy ....... they've got nothing to hide ........
 
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yeah I could see they were a cheap copy straight away which is just what I would expect from Atomik. They just keep living up to that great reputation they have ha ha ha ha
 
the frame looks good quality to me
i think cactus was reffering to themountains comment maybe
 
my frame looks similiar in pics
look at some of the holes in the frame u can see the machining
 
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