Forkless is back!
Before I get into the new project, first a quick personal update. I didn't post much last year as I was super busy with a second job. I was hired by an e-moto startup to do the chassis design work for their electric motorcycle project. To date, we've completed a beautiful prototype, but unfortunately the company has now run low on funds and doesn't want to show the bike publicly yet. I was hoping I could share some pics, but those will need to wait.
In the little bit of spare time I've had, a little bit of work has been done to get one of my AK-1s back on the road, and I've gotten my RZ250R out of moth balls and running again. Got two other RZ350 that are getting partial restorations, but nothing really too crazy.
As for some older projects... FOSMC II (Snap-together Ducati) is still on hold. AK-1 (prototype 1) full restoration rebuild is also on hold. And my RZ500 project is still on hold, but I look at it screaming back at me every weekend.
Okay, on to the current new project... Over the years I've had lots of people ask me about building custom RZ350 frames. Some are serious, some less serious, but so far none have made a commitment. None the less, its a project that has always been of high interest (see sketches below). Last year, I decided that I wanted my next Dirtbag Challenge build to be based on an RZ350 so I began sketching some ideas for a chassis with a crazy girder fork design with low mounted dual shocks (sketches below). So kind of a theme here in that for the past few years I've made lots of sketches of semi-trellis framed RZs.
Fast forward to last week and out of the blue a friend sends me this picture of SXR600 race bike with a one-off trellis frame. Holy shit... thats got so many similarities with the frame I want to build! So that was the kick I needed to decide to make this a reality. The plan is to use this year's Dirtbag Challenge as a prototype build (minus the crazy front end), then maybe add the front end for next year's DBC.
More specifically, there are three major flaws with the RZ350 frames that I hope to address. First is the 80s era geometry. At 26 degrees rake and relatively short swingarm there is potential to greatly improve the overall layout. Second is the rear suspension design. Again, the 80s era design relies heavily on motocross technology of the era and results in a linkage geometry that is overly progressive. Lastly is the physical location of the suspension linkage which hangs very low. This is a problem when routing expansion chambers. A design with the shock and linkage positioned higher will result in much better clearance with the pipes.
I think its funny that there have been many attempts by many people to improve RZ frames, but most just end up adding un-needed braces which just adds weight without addressing the real issues in need of improvement.
design sketches for past few years:
[/url]20190303_182636 by andbike, on Flickr[/IMG]
[/url]20190303_182704 by andbike, on Flickr[/IMG]
[/url]20190303_182929 by andbike, on Flickr[/IMG]
[/url]20190303_183018 by andbike, on Flickr[/IMG]
[/url]20190303_181020 by andbike, on Flickr[/IMG]
[/url]20190303_181127 by andbike, on Flickr[/IMG]
[/url]20190303_181149 by andbike, on Flickr[/IMG]
This is the SRX600 that is acting as inspiration (not my bike):
[/url]DSC_0368 by andbike, on Flickr[/IMG]
[/url]SRX_Racer2 by andbike, on Flickr[/IMG]
Stay tuned for more...
Before I get into the new project, first a quick personal update. I didn't post much last year as I was super busy with a second job. I was hired by an e-moto startup to do the chassis design work for their electric motorcycle project. To date, we've completed a beautiful prototype, but unfortunately the company has now run low on funds and doesn't want to show the bike publicly yet. I was hoping I could share some pics, but those will need to wait.
In the little bit of spare time I've had, a little bit of work has been done to get one of my AK-1s back on the road, and I've gotten my RZ250R out of moth balls and running again. Got two other RZ350 that are getting partial restorations, but nothing really too crazy.
As for some older projects... FOSMC II (Snap-together Ducati) is still on hold. AK-1 (prototype 1) full restoration rebuild is also on hold. And my RZ500 project is still on hold, but I look at it screaming back at me every weekend.
Okay, on to the current new project... Over the years I've had lots of people ask me about building custom RZ350 frames. Some are serious, some less serious, but so far none have made a commitment. None the less, its a project that has always been of high interest (see sketches below). Last year, I decided that I wanted my next Dirtbag Challenge build to be based on an RZ350 so I began sketching some ideas for a chassis with a crazy girder fork design with low mounted dual shocks (sketches below). So kind of a theme here in that for the past few years I've made lots of sketches of semi-trellis framed RZs.
Fast forward to last week and out of the blue a friend sends me this picture of SXR600 race bike with a one-off trellis frame. Holy shit... thats got so many similarities with the frame I want to build! So that was the kick I needed to decide to make this a reality. The plan is to use this year's Dirtbag Challenge as a prototype build (minus the crazy front end), then maybe add the front end for next year's DBC.
More specifically, there are three major flaws with the RZ350 frames that I hope to address. First is the 80s era geometry. At 26 degrees rake and relatively short swingarm there is potential to greatly improve the overall layout. Second is the rear suspension design. Again, the 80s era design relies heavily on motocross technology of the era and results in a linkage geometry that is overly progressive. Lastly is the physical location of the suspension linkage which hangs very low. This is a problem when routing expansion chambers. A design with the shock and linkage positioned higher will result in much better clearance with the pipes.
I think its funny that there have been many attempts by many people to improve RZ frames, but most just end up adding un-needed braces which just adds weight without addressing the real issues in need of improvement.
design sketches for past few years:
This is the SRX600 that is acting as inspiration (not my bike):
Stay tuned for more...