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re_animate
6th July 2013, 23:49
Picked up a gn250. I will make a bobber out of it.

Step one is to replace the rear springs with solid struts to hardtail it.
Looked online and struts will cost me $110, which is crazy, I ain't spending that much on a gn.

For the time being, I want to do a proof of concept so I'm looking at alternative strut materials that will hold up, looks do not really matter at this stage.
I'm thinking of heading into mitre10 and picking up some fairly thick copper pipe, drilling holes on either end (paint it black) and installing that to see how it looks.

Question is, will the copper pipe handle alright under weight load? - Dont want to ride it and have them bend when I hit a bump, that would be stupid.
or what are some good alternative options.


attached image is $110 struts - 25cm from centre of hole to hole, holes are 1.3cm dia + wall

hayd3n
7th July 2013, 00:44
Picked up a gn250. I will make a bobber out of it.

Step one is to replace the rear springs with solid struts to hardtail it.
Looked online and struts will cost me $110, which is crazy, I ain't spending that much on a gn.

For the time being, I want to do a proof of concept so I'm looking at alternative strut materials that will hold up, looks do not really matter at this stage.
I'm thinking of heading into mitre10 and picking up some fairly thick copper pipe, drilling holes on either end (paint it black) and installing that to see how it looks.

Question is, will the copper pipe handle alright under weight load? - Dont want to ride it and have them bend when I hit a bump, that would be stupid.
or what are some good alternative options.


attached image is $110 struts - 25cm from centre of hole to hole, holes are 1.3cm dia + wall
copper seriously??

get some steel pipe instead

DrunkenMistake
7th July 2013, 00:55
coppper seriously??

get some steel pipe instead


As above,
If you are considering using copper pipe,
PLEASE put down the tools.

If you want to get an idea of a good length for ride height I would suggest two lengths of wood with a series of holes drilled in them so you can adjust to find a good height,
Then going from there.

You could explore CNC'ing some Aluminium struts, but as looks arnt a big thing I would go to your local steel supplier and pick up some rod and going from there.

blackdog
7th July 2013, 01:35
Fork out the $110.

I'm not sure you even have the aptitude to be a blacksmith, nevermind a motorcycle fabricator.

My money would be on the smith's struts, either way.

bogan
7th July 2013, 02:20
Looked online and struts will cost me $110, which is crazy, I ain't spending that much on a gn.

To properly mod a bike you either need a lot of money, or a bit of time and access to gear and knowledge to use it correctly. For what they are, and the finish on them, 110 sounds about right. Copper pipe with holes drilled will be a lot weaker, both the material, and its physical design.

jonbuoy
7th July 2013, 03:37
I like the look of polished copper as well but don't try and use it for anything structural. If you want the copper look just use a length of thin wall plumbing pipe as a decorative sleeve over your struts. You do not want those struts bending, you will need something rigid like steel tubing. I wouldn't use flat bar. If you dont have a welder you might get away with some thick threaded steel rod inside a length of strong steel tube - that way you can use something like a rose joint on either end and some lock nuts to keep the bar and tube in tension- it will be pretty rigid. You can the slip the copper pipe over the steel pipe for looks. Take a look at your own shocks for an idea of how heavy duty the bar needs to be. If you go with rose joints just check there's no sideways play or the swing arm will be able to move sideways. I just did something similar for a set of anti tramp bars.

re_animate
7th July 2013, 09:12
Lol, ok so copper pipe is off the table.

I've emailed a few local steel shops to find out prices of steel pipe.
Would a steel block with holes either end work structurally? (see attached image)

Anyond know what should I expect to pay for a pipe 20mm in diameter x 520mm long with a hole that's 13mm?
Would I be better off just buying the prefab strut online?

jonbuoy
7th July 2013, 09:28
Thats a serious block of steel - pretty hefty in weight. I would buy them ready made up.

skippa1
7th July 2013, 09:43
Question is, will the copper pipe handle alright under weight load? - wall

I would suggest that if you are serious with this question, you do not have the necessary basic skills to attempt any customisation and you should step away from the bike.

Drew
7th July 2013, 10:28
So, with less sarcasm. No, copper pipe is not strong enough.

Drilling a hole through any pipe and bunging a bolt through is not strong enough period. If you go with that method, it needs another smaller piece of pipe through the drilled hole, and welded around where the two come together.


Best look, is to drill a hole the same size as the pipe. Essentially that cuts the pipe but leaves a nice curve for another piece of pipe to sit nice and snug in the cradle. Bush it to the right size for your bolt, and you have exactly what the $110 would have bought you.

Dunno about what your time is worth, but if I had the money doing nothing, it's cheaper to buy than build.

jellywrestler
7th July 2013, 11:08
Lol, ok so copper pipe is off the table.


copper was never on the table as it wont even hold a table up far less a motorcycle over bumps!!!!

jellywrestler
7th July 2013, 11:11
Picked up a gn250. I will make a bobber out of it.

Step one is to replace the rear springs with solid struts to hardtail it.
Looked online and struts will cost me $110, which is crazy, I ain't spending that much on a gn.

For the time being, I want to do a proof of concept so I'm looking at alternative strut materials that will hold up, looks do not really matter at this stage.
I'm thinking of heading into mitre10 and picking up some fairly thick copper pipe, drilling holes on either end (paint it black) and installing that to see how it looks.

Question is, will the copper pipe handle alright under weight load? - Dont want to ride it and have them bend when I hit a bump, that would be stupid.
or what are some good alternative options.


attached image is $110 struts - 25cm from centre of hole to hole, holes are 1.3cm dia + wall

why not drill a hole in the top of your shocks and empty the oil out, flush it out with meths then fill it up with plaster of paris when it sets then you will have the hardtail of your dreams.....

tigertim20
7th July 2013, 11:19
firstly, as said, dont use copper.

go to a steel supplier and ask them what lengths of damaged stock they have - theyll sell it to you by the metre, wont cost you more than $20.'

secondly if you want to figure it out without spending the coin, then 'acquire' a copy of photoshop, and spend some rainy evenings trying things out to see how it would look

The Reibz
7th July 2013, 13:09
20mm is overkill. Take your drawing to Autobend or any laser cutting shop and get them to cut it from 12mm mild steel flat bar.

If I had a drill press in my shed I would cut these out with my plasma and drill the holes for 60 bucks. $110 is reasonable so I would just buy those...

re_animate
7th July 2013, 17:08
Yeah, fair enough. I think I might just buy the struts rather than waste time looking for cheaper options.

By the way, I'm new to the whole modifying motorbikes thing. I've got no one teaching me but youtube. I figured copper plumbing pipe was a stretch, just looking for alternatives to a part that seemed a bit more expensive than it's worth. So didn't mean to sound incompetant, I'm just inexperienced with motorbike frames. - I've worked on engines before, just wanted advise on saving some cash from people who had experience.

So no, I will not step away from the bike haha.

Another question, where would be a good place to get a solo seat? I haven't had any luck finding them anywhere

Drew
7th July 2013, 17:31
Another question, where would be a good place to get a solo seat? I haven't had any luck finding them anywhereThe coolest ones, are hand made. In this area, I'd make my own and have it covered.

Uber cool is an old style tractor seat, but prolly a bit bulky on the GN.

jonbuoy
7th July 2013, 18:42
Don't sweat it - no one is born with experience gotta start somewhere.

BIG DOUG
7th July 2013, 19:03
Shit I think I have some of those biltwell struts in the garage somewhere.

Road kill
7th July 2013, 19:20
Remove the springs from the standard shocks then fully compress the shock and weld the top to the shock body.

I did it with a pair of CB550 shocks I used for a slightly different application years ago.

AllanB
7th July 2013, 19:32
I usually apply the theory if I have nothing nice to say, then shut-up.

But in this case I figure that if you are even considering copper pipe, then you are not capable to be altering anything on the bike little-lone oiling the chain. FFS $110 is very reasonable. If you do not have the foresight to realise this now then go back to your PlayStation.

bogan
7th July 2013, 19:39
Yeah, fair enough. I think I might just buy the struts rather than waste time looking for cheaper options.

By the way, I'm new to the whole modifying motorbikes thing. I've got no one teaching me but youtube. I figured copper plumbing pipe was a stretch, just looking for alternatives to a part that seemed a bit more expensive than it's worth. So didn't mean to sound incompetant, I'm just inexperienced with motorbike frames. - I've worked on engines before, just wanted advise on saving some cash from people who had experience.

So no, I will not step away from the bike haha.

Another question, where would be a good place to get a solo seat? I haven't had any luck finding them anywhere

There's only so much you can learn form youtube; I think you really need some more hands on experience or work with someone who has it, before getting stuck in on a project which is so critical to your road safety.

re_animate
7th July 2013, 21:26
Why all the flaming? I'm trying to find a cheaper temporary alternative to a relatively expensive part, and if that fails I'll go for the actual part. That's a pretty logical thing to do, damn.

I'm curious, what about bicycle framing? - I think it's aluminum. That's pretty easy to obtain.

skippa1
7th July 2013, 21:34
Why all the flaming? I'm trying to find a cheaper temporary alternative to a relatively expensive part, and if that fails I'll go for the actual part. That's a pretty logical thing to do, damn.

I'm curious, what about bicycle framing? - I think it's aluminum. That's pretty easy to obtain.

Nobody is flaming you but the suggestions you are making clearly indicate that you're engineering ability is very limited, I have only seen constructive criticism that may save your life or the life of someone else on the road. What you have suggested indicates you don't have the required skills to safely modify the bike.

DrunkenMistake
7th July 2013, 21:38
Why all the flaming? I'm trying to find a cheaper temporary alternative to a relatively expensive part, and if that fails I'll go for the actual part. That's a pretty logical thing to do, damn.

I'm curious, what about bicycle framing? - I think it's aluminum. That's pretty easy to obtain.


Just go and buy some steel mate and any other minor stuff needed pop into an engineering firm on their lunch break, look for the fella out the front having a fag and offer him some cash to weld or cut or drill what needs done,
Or buy the pre-fabbed part.

If you reallyyyyyy want to do it yourself you could try some box section, its cheap enough and would be strong but before considering that option do some research into it, im not 100% sure it would be enough someone on here might have a better idea.

buggerit
7th July 2013, 21:39
FFS step away from the tools:facepalm:Mate you are a worry, try and find some with some skills that can give you some hands on help otherwise you
are going to be disappointed, out of pocket and maybe injured.

re_animate
7th July 2013, 21:43
Lol yeah, I'll admit I have no idea how much load will be on the spring strut, or the load bearing capabilities of steel vs copper pipe or aluminum. Fair enough, I guess I am being a little too cheap, probably not worth the probable danger.

tigertim20
7th July 2013, 22:18
given your admission around your limited experience, try mucking around with some smaller, less important bits and pieces before fucking with a frame in a manner that could kill you or someone else if you get it wrong.

re_animate
8th July 2013, 18:09
Will cost me round 60 for the steel alone. I've bought the actual struts so that's not going to be an issue any more.
Anyone got any good resources on making a solo seat? - What's the actual name for them?

DrunkenMistake
8th July 2013, 18:31
Will cost me round 60 for the steel alone. I've bought the actual struts so that's not going to be an issue any more.
Anyone got any good resources on making a solo seat? - What's the actual name for them?

What style of seat are you going for mate?

Sable
8th July 2013, 18:55
What style of seat are you going for mate?

One with a dildo attached because he's a noob on a GN.

re_animate
8th July 2013, 19:35
What style of seat are you going for mate?

i'm thinking this: http://cycleshackparts.com/Ultima%20Seat.jpg

Road kill
8th July 2013, 19:45
Will cost me round 60 for the steel alone. I've bought the actual struts so that's not going to be an issue any more.
Anyone got any good resources on making a solo seat? - What's the actual name for them?

A couple of different people on Trade Me have them listed.

Both from Builtwell and Dime city.

Their called seats,,,;)

AllanB
8th July 2013, 20:07
A solo seat will cost you $110 ...........

Coolz
8th July 2013, 21:44
Send Robert Taylor a PM. I'm sure he'll give you some helpful advice.:lol:

hayd3n
8th July 2013, 22:25
cheap /retro look ,go get a old style bicycle seat think 50's


and the seat ur referring to is called a springer/solo seat
http://stores.ebay.com/CycleExprezz/16-SOLO-SEAT-KITS-/_i.html?_fsub=2250372014