Monday, May 23, 2011

/2 swingarm conversion










The /2 swingarm conversion has started. Matt helped me press the driveshafts apart today. I tried my small gear puller, but it was soon pretty obvious that I would need to use the hydraulic press. I had to heat the r75/6 driveshaft to get it to finally "pop". Both driveshafts really "popped" when they finally let go. It was quite startling how much pressure it took to release things.

The plan is to graft the larger /6 housing onto the /2 swingarm. Then I will be able to use the stronger /6 driveshaft and final drive in the /2 frame. This is supposed to make the bike stronger for sidecar use as well as larger engine choices. My /6 final drive is in decent shape with a small amount of wear on the teeth and the gearing (37/11) should be good, especially if I use a large engine like an r80/r90/ or r100. Next thing to do is to make a jig to secure the swingarm for welding. This is going to take some work to ensure proper alignment, but I've contacted Brock Downey (he has made several of these) and he has given me some great advice.



13 comments:

Klezmoris said...

Did you build the jig?
Any followup pics?

Frankie Flood said...

Yes, I built the jig. The following links may give some insight into what I did. Are you building a conversion? A lot of people just use the /2 swing arm, and turn down the /6 driveshaft coupler so it doesn't rub inside the swing arm housing. I probably could have done that instead.

http://frankieflood.blogspot.com/2011/05/2-conversion-swingarm.html

http://frankieflood.blogspot.com/2011/07/2-shock-bracket.html

http://frankieflood.blogspot.com/2011/07/2-swingarm-conversion.html

http://frankieflood.blogspot.com/2011/06/welding-jig.html

http://frankieflood.blogspot.com/2011/07/2-swingarm-conversion.html

Klezmoris said...

Now that's really helpful thank you!
I decided to go the later final drive route, as my donor engine is the big valve 1000 off a '77 RS and I suspect that a /2 drivetrain wouldn't be able to handle the torque.

Frankie Flood said...

That makes sense. I would love to "follow" along on your conversion. Please let me know if you happen to document the building. I still have a bit to do on mine and would like to move up to a larger donor engine in the future. Also, let me know where you live. I still have the jig I built and I could send it to you as a loaner if you happen to want to borrow it.

Klezmoris said...

That's very generous of you, but the freight to South Africa will kill the gesture!
My wife's cousin was visiting here from Toronto and I had her all lined up to take a pre-addressed package and drop it in the mail to Brock Downey..but she backed out at the last minute..hence the resurged interest in a DIY job.

Frankie Flood said...

Yikes! Yes, South Africa might be a little tough. Well regardless, let me know if you need me to take any measurements off of my jig. Keep me posted on your progress!

Gmac said...

Frank, thanks for the pictures and postings it really helps with my project as well. I am basically doing the same thing would you be willing to build another one? I have all the parts but lack the tools and the shop. Converting a 74 r90/6 to a 55 r50/2.
Gmccaslin68@gmail.com

Gmac said...

Frank, thanks for the pictures and the postings. I am building r50/2 with a r90/6 motor. Basically looking for some options on the swingarm. Want to use my /6 drive. Would you consider making another one? I have all the parts but lack the skills and tools.
Gmac

Unknown said...

If you are willing to do even another I am undertaking a conversion project and want to update the swing arm. I have someone who might help me with it here in Lexington but if you could do it I would be happy to pay you to do so as your work looks great.

tim in KY

Frankie Flood said...

Hi. I'm just not able to help at the moment as i just have too many things on my plate. So sorry.

Unknown said...

Thanks for the response, I have been in contact with Brock and am trying to get everything together to have him do this, or I might attempt myself.

Big fan of your blog, everything from the BMW's to the VW's to the Land Cruisers, great taste in machines you have.

And you have inspired me to post more in my blog, thanks again and keep up the great work.

Frankie Flood said...

Thanks +timmy tonti. Brock will do an amazing job. I look forward to watching your blog.

Thank for your kind words. My wife says she needs psychiatric help due to my taste in machines... I think she'll get over it though.

PaulB said...

Hi there,

Are you offering this fabrication service? The only other group I found doing this is using a CNC component to weld on which I don't like the appearance of. I have both /7 and /2 swingarms.

Paul

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