Makin a Chassis?

chef.tay · Posted: October 4, 2009, 7:45 pm Post subject: Makin a Chassis?

Okay guys,

How should i go about making a chassis for a chopper project?

I want it to be just plain and simple and nasty but still strong

Thanks

Chef.tay

Teebs · Full Member Joined: Aug 26, 2008 Posts: 255

Well, that narrows it right down. lol

chef.tay · Posted: October 4, 2009, 8:32 pm Post subject: Re: Makin a Chassis?

I just need instruction on what to use to make a frame from scratch haha

Teebs · Full Member Joined: Aug 26, 2008 Posts: 255

Well, that's the nice thing about making your own frame. You can use pretty much whatever you want as far as O.D. goes. I'd stick with .120 wall DOM tubing. You want to start with a stock neck. The backbone should be 1.5" OD minimum, and the stock rails on a XS are 1 and 1/8" so that should be the minimum for downtubes and seat rails etc.

Do you have any welding or fabricating experience? What do you have available for equipment? If you're going to build a custom frame, you should consider building a jig first and if you only plan on using it once somebody will buy it from you when you're done.

Plans for a nice jig: www.crimescenechoppers.../jigplans/

Of course, the jig doesn't need to be this detailed, you can simplify the plans based on wheel width, rake, and stretch etc., and just make them fixed rather than adjustable. The main thing is to understand motorcycle geometry, rake and trail, and the importance of keeping everything as straight as possible.

Teebs · Full Member Joined: Aug 26, 2008 Posts: 255

Also, you may have much more success getting responses to this question on thechopperunderground.com

chef.tay · Posted: October 4, 2009, 9:05 pm Post subject: Re: Makin a Chassis?

Ohkay i'll check that place out.

I have all the equipment that you'd find in a sheet metal shop available to me but i don't have any experience welding so far. I'm planning on learning as i go, i guess you could say.

would it be a good idea to get the engine and then build the frame around that( so to speak)?

roar · Full Member Joined: Sep 15, 2008 Posts: 54

What would be a really good idea is not to try and gain your welding experience making a motorcycle frame. Build a shelf or something, but let a pro build the frame. In the end it's your ass though.

Roar

Teebs · Full Member Joined: Aug 26, 2008 Posts: 255

That was why I was asking about your experience, chef.tay. This is not really a project for an inexperienced builder.

Too many of our brothers die because of other people's stupidity without risking our own necks with unsafe rides. Please be safe. I'm not trying to be a dick or condescending.

If you haven't already you should talk this over with an experienced bike fabricator in your area. He will be able to explain all of the variables involved in building a safe, reliable frame.

I'm not trying to talk you out of it, just make sure you're fully educated on the subject, and when you do it... let a professional welder do the actual welding. Tack weld it together and pay somebody to make sure all of your welds aren't going to break apart under the constant flex and stresses that a motorcycle has to endure.

despecial · Posted: October 5, 2009, 12:39 am Post subject: Re: Makin a Chassis?

CT back in the early 70s when i built my first chopper in the garage at home using a small arc welder and very little else, there were no forums like this-no computers either for that matter-and info was rarer than hens teeth
it was an interesting learning curve, but then when youre that age the world seems carefree and risk could be avoided with speed and a condom - now im over 50 and in retrospect somewhat amazed ive got here-many didnt
my point? in this new world of information sharing and transferrable knowledge you can begin to learn from others mistakes if you ask and keep an open mind - the process wont always be smooth but hey the advantage may just be enough to save your ass...
go to night school-do a course in welding and practise, modern mig and tig welders are great-start small, think big

yamaman · Posted: October 5, 2009, 6:57 am Post subject: Re: Makin a Chassis?

Finally a couple of inteligent & mature responses to this question, well said Teebs & despecial.
To many times this & similar questions have been asked & met with extremely hostile & uninformed responses. Usually from people with no experience in actually making/modding a frame! Cheers fellas

roar · Full Member Joined: Sep 15, 2008 Posts: 54

Didn't know my response was unintelligent and immature. Chef.tay, didn't mean for my comment to come off as hostile, but it was meant to point out that learning to weld on a bike frame isn't a very bright idea.

No hard feelings,
Roar

yamaman · Posted: October 5, 2009, 9:08 am Post subject: Re: Makin a Chassis?

Sorry roar, was not at all, in any way, directed to you!

Same topic has come up a number of times before, with some poor responses.

The right student, along with the right teacher, could build a frame that was up to scratch. But for sure, if you've no idea & you just buy a few lengths of tube & a welder, your looking for trouble.

It's right to point out the facts/dificulties to any budding builder. Just no need to get up on your soap box & dictate your opinion! & this has occured in the past. Just pointing out that I like the way this thread has gone so far. Cheers

roar · Full Member Joined: Sep 15, 2008 Posts: 54

No worries Yamaman,

You're right though, a good teacher and the right student could pull it off. The big thing being the teacher there to notice and point out any errors or flaws. This teacher should have a some bike know with all as well.

I've built a few trailers, docks, boatlifts, and various other projects to have enough knowledge to be dangerous to myself building a bike frame. Not because I doubt my welding, which I should, but because I've never built a frame. With something that can be so "life and death" it's best to learn with hands on guidance rather than online researching and/or trial and error.

Best of luck,
Roar

chef.tay · Posted: October 5, 2009, 12:06 pm Post subject: Re: Makin a Chassis?

This is perfect to what i was looking for. I didn't know if it was a good or bad idea to even attempt it so thanks a lot!

I would like to try and build one but it'd be a big project. Are there any stock frames that work well for choppers that you guys know of?

Srinath · Posted: October 5, 2009, 12:59 pm Post subject: Re: Makin a Chassis?

A savage 650 is well spread out, pretty light and very low, I also have chopped one with raked triples and a dirt bike front end.
I have pics posted here somewhere ...
charlotte.craigslist.o...01096.html
Cool.
Srinath.

yamaman · Posted: October 5, 2009, 2:11 pm Post subject: Re: Makin a Chassis?

Some good reading here for building frames:

www.eurospares.com/frame.htm

chef.tay · Posted: October 5, 2009, 4:14 pm Post subject: Re: Makin a Chassis?

www.xs650chopper.com/w.../08/12.jpg

Here's what i'm lookin for..

Teebs · Full Member Joined: Aug 26, 2008 Posts: 255

That is a stock XS650 frame with the rear half cut off and a hardtail welded on.

You can purchase a weld-on hardtail from TC Bros. choppers and G&L choppers, among other places. They also do the hardtailing for you, or you can buy one of their frames.

Srinath · Posted: October 6, 2009, 2:54 pm Post subject: Re: Makin a Chassis?

Srinath wrote:

A savage 650 is well spread out, pretty light and very low, I also have chopped one with raked triples and a dirt bike front end.
I have pics posted here somewhere ...
charlotte.craigslist.o...01096.html
Cool.
Srinath.

Ooooo this looks like someone has already implemented this idea.

www.xs650.org.au/offbeat.html - scroll down to where they call a bike the "world's ugliest xs650 rat bike".
That is a savage frame an near as I can tell. Better pics would help.
Cool.
Srinath.

Srinath · Posted: October 6, 2009, 2:55 pm Post subject: Re: Makin a Chassis?

OK maybe not, cant tell form that pic though ...
Cool.
Srinath.

Teebs · Full Member Joined: Aug 26, 2008 Posts: 255

Srinath, that's a hacked up XS frame for sure. You can tell by looking at the area on the frame where the swingarm mounts.

Srinath · Posted: October 6, 2009, 3:26 pm Post subject: Re: Makin a Chassis?

Teebs wrote:

Srinath, that's a hacked up XS frame for sure. You can tell by looking at the area on the frame where the swingarm mounts.

I realised that almost as soon as I had posted ...
I however figure the xs motor will fit in the savage frame though.
I have a spare motor and a spare savage frame, tight to stuff em and get a pic ...
Cool.
Srinath.

Teebs · Full Member Joined: Aug 26, 2008 Posts: 255

My nephew won a Kikker 5150 Hardknock in a raffle and I've thought MANY times about trying to stuff an XS650 motor in there. I'd have to alter the backbone and I'm not completely confident that the frame would handle the stress, but it would be fun to find out!

KIKKER 5150 HARDKNOCK

Srinath · Posted: October 6, 2009, 3:45 pm Post subject: Re: Makin a Chassis?

That looks rather small.
Cool.
Srinath.

What Happened to 650rider.com?

Yamaha xs650