RZ350 re-frame... classic 2-stroke gets modern upgrade

[Frame Maker]

I don't know how I missed this thread, but I'm glad I found it.

I'm excited to see the progress Julian!

What the hell Josh? Well, I'm glad you found this thread... and your name should be at the top of the list for potential track test riders

PS- what's your preferred seat height on those yellow bikes you ride?

 

[Frame Maker]

This past week's progress:

With the 3D prints now in hand, it's time to build a mock-up of the mid-frame and see how it fits to an RZ350 engine. In the shop I turn the cross tubes for the mid-frame. Some scraping with a utility knife is needed to smooth and remove a small amount of material from the 3D prints to get the aluminum cross tubes to a nice press fit. The 1/4" plate engine mounts and lower suspension mounts have already been laser cut a few weeks ago.

20210206_161119 by andbike, on Flickr


My aluminum welding skills are virtually non-existent, but I manage to tack weld the plates to the tubes and assemble the mock-up.

20210207_113335 by andbike, on Flickr

20210207_113403 by andbike, on Flickr


With the mid-frame mock-up completed, time to see how it fits... Oh Shit! It kinda doesn't fit. Well, this is exactly why I made the 3D prints before spending real money on CNC machined aluminum parts. So I'm glad to catch this interference early.

There is an area where the 3D printed side plate is interfering with the clutch cover. Using my Dremel with a small saw, I trim away some material and now the mid-frame will fit, although I don't like how the clutch cover is now captured under the plate and can't be removed with the engine in place.

20210207_142245 by andbike, on Flickr

20210207_150045 by andbike, on Flickr

I'll readdress this issue later and possibly make some design changes to the side plate. On the left side there is an interference with the left side engine cover. If I use the original RZ350 side cover the interference is significant, although the left side covers are plastic and can be trimmed. The interference is only in the area that covers the c/s sprocket so nothing structural or containing fluids would be compromised. If I swap to a Banshee left side cover the interference is very minimal. The RZ side covers are getting scarce while the Banshee covers are still available from Yamaha. So that will be the solution.

Also this past week more laser cut brackets arrived so I can finalize the seat mounts. I love how they blister pack everything so nothing falls out of the packaging. I've used laser cutting vendors in the past who possibly never had customers from remote locations and their packaging was horrible. Anyway, the flat brackets are easily formed to final shape.

20210207_134904 by andbike, on Flickr


One bracket is for the center tongue on the seat. The other brackets are for the rear screw mounts. The rear brackets are intentionally long and require some sanding to remove material for final fit.

20210208_121011 by andbike, on Flickr

20210208_132508 by andbike, on Flickr



Then a few tack welds to confirm fit, followed by final welding and the seat is ready to be mounted.

20210208_141213 by andbike, on Flickr

20210208_143347 by andbike, on Flickr


When I first started building frames I would use rivet-nuts any place where I couldn't access the back side to place a normal nut. Now I like to use these clip-nuts. They work very well and if they ever get stripped or damaged just throw away and use another one. Super handy.

20210208_160246 by andbike, on Flickr


I have a fiberglass tail for a KTM cup bike that I like the shape, however it doesn't fit to the R6 seat very well. For now I'll use a Yamaha replica tail just to see how the bike will look with a race tail. At first I try one based on 99-02 R6 to see how it looks.

It looks much better than the utility rack I had used for the Dirtbag ride, but it still looks kinda clunky.

20210209_114305 by andbike, on Flickr

20210209_114644 by andbike, on Flickr

Next I try a replica tail for a 03-05 R6. Its a little lower and seams to follow the styling of the tank much better. This is an improvement and I'm finally starting to get aroused by how the bike is lookingarty

20210209_145410 by andbike, on Flickr

The long term goal is to sculpt a tail that fits properly to the R6 seat, but has the rear portion based on the KTM cup bike tail. But that effort will wait. For now the priority is getting the frame re-design finalized.


More to come...

 

[kpke]

This is looking excellent. Really quite unbelievable to start with metal tubes (and other things), get bits and pieces ordered and fabricated from all over the world, and end up looking like this. Thanks for the update.

If I may ask, why a wizard fabricator welder dude like you has difficulty with welding aluminum?

 

[auntiebling]

That laser vendor has been pooping up on my facebook feed... I just dont need to laser cut stuff I want to try!

 

[bikewanker]

Even with more coffee it’s mostly beyond my comprehension how you’re fabricating a frame Julian! Have enjoyed following this process. For me it’s kinda like a Playboy magazine, I gots to have pictures to understand.
Thank you.

 

[bobl]

Looking great! I like the 03-06 r6 tail the best. Do you have any idea of what the final weight well be? Will it be a track only bike or road registered? Amazing work!

 

[Frame Maker]

...If I may ask, why a wizard fabricator welder dude like you has difficulty with welding aluminum?

Welding steel and welding aluminum are different in how the material reacts to heat. When I first learned to weld I did a lot of body repair on old VWs. Everything was always steel. I got confident with steel. Then when I started to build motorcycles I wanted the aluminum parts to be perfect and was introduced to Dennis Etcheverry at Norman Racing. His aluminum welding is some of the best I've ever seen. I don't need aluminum welded very often so I just keep going back to Dennis whenever I have aluminum parts to weld.

20170815_125630 by andbike, on Flickr

That laser vendor has been pooping up on my facebook feed... I just dont need to laser cut stuff I want to try!

Their minimum order amount is only $29 (for most materials) and includes 2-day shipping to the bay area. So its pretty cheap even if you just want to experiment. They've recently added carbon fiber sheet, so maybe heel guards or some simple accessory for a moto project would be easy if you want to try it out.

Even with more coffee it’s mostly beyond my comprehension how you’re fabricating a frame Julian! Have enjoyed following this process. For me it’s kinda like a Playboy magazine, I gots to have pictures to understand.
Thank you.

Ha! I like your Playboy pictures analogy! Thanks!

 

[Frame Maker]

Looking great! I like the 03-06 r6 tail the best. Do you have any idea of what the final weight well be? Will it be a track only bike or road registered? Amazing work!

Thanks

Yep, the general consensus is the 03-06 tail, so that will stay on... for now.

Using a bathroom scale I have the wet weight (tank partially full) at about 285 lbs with approximate 54/46 distribution front to rear. With the utility rack gone, it is likely a little less right now.

The bike is titled and street legal. I've already ridden about 600 miles on it. Since I'm reconstructing the rear sub-frame the tail light and license plate are off right now. A few pages back in the thread I discuss the DMV / CHP / inspection process. I also hope to do some track testing.

20201013_130305 by andbike, on Flickr

 

[auntiebling]

Their minimum order amount is only $29 (for most materials) and includes 2-day shipping to the bay area. So its pretty cheap even if you just want to experiment. They've recently added carbon fiber sheet, so maybe heel guards or some simple accessory for a moto project would be easy if you want to try it out.
!

that's good to know, thanks!

 

[Joshman]

What the hell Josh? Well, I'm glad you found this thread... and your name should be at the top of the list for potential track test riders

PS- what's your preferred seat height on those yellow bikes you ride?

Ooh, yes I'd love to test it out!

I've been playing around with seat height. I'll measure it this weekend and get back to you.

 

[GPzPop]

Dennis E is truly a master welder, he has helped me out with a few repairs

 

[Frame Maker]

I just finalized the last CAD revisions to the CNC machined parts. I fixed the engine interference and moved the engine 3mm forward just to give a bit extra clearance. Then sent off an RFQ to my secret Chinese vendor. Fingers crossed.

 

[Frame Maker]

Here's another quick update: The quote came back from my Chinese vendor and it was more than double what I was expecting. Not unreasonable, but not super cheap as before. What really got me depressed was that I was counting on the very low cost so that the frames could be made and sold for decent profit if I get to a point of reproducing them. This new pricing would kill that possibility if I stay with the current design.

My wife told my to wait 24 hours and sometimes a solution will come. So I waited a day before notifying the CNC vendor that I wouldn't be able to continue. I noticed that a few of the parts that were very similar to ones they had made back in August were double and one was even triple the cost even though the parts hadn't changed very much. I mentioned this to my contact person and she replied that they had a new person(s) doing the the quoting and to ignore the quote. She said a new quote would be sent. Sure enough a new quote came an hour later with prices back down to the very favorable level I had expected. Back in business!

Yesterday, I made one more quick fit check with the 3D prints. When I removed the left front engine mount it was badly galled from rubbing on the power-valve pulley housing. A few washers under the bracket solved the problem, so I added the same thickness of 3mm to the CAD model so that the new engine mount would sit proud and just clear the pulley cover. I sent off the revised CAD for that part to see how much the price would change. Turns out no change in price. So, then sent off a PO for 3 complete sets of CNC machined aluminum bits.arty

One thing I miss from my days in art school is getting good feed back from other designers. So a few weeks ago I reached out to my friend Greg Tada. We both studied transportation design at Art Center and Greg is now working as a professional motorcycle designer. In his free time he is working on an ambitious personal project converting a GTS1000 to electric power and adding some very modern bodywork. So far he hasn't built anything real, but he's got a really nice CAD model of his project. Anyway, Greg and I did a Zoom call last night and had great time critiquing each other's work. Greg has a good eye for the aesthetics and was able to provide some good feedback on my design. He really likes the overall aesthetic, but had some suggestions to help balance some of the visual impact of the CNC aluminum parts which will become strong focal points of the revised design. I on the other hand have 30+ years experience fabricating motorcycles and was able to give Greg some valuable suggestions on how he might fabricate portions of the chassis that he plans to modify. I was also able to provide some feedback on his styling as well. Anyway, it was super cool talking designer to designer.

I'm guessing most people won't know who Greg is, but you might recognize some of his more recent work...

 

[bikewanker]

A story of patience and sharing knowledge. A good bit of positive humanity in your progress!

 

[MikeGyver]

You're having all the fun! I'm jealous.

 

[bobl]

I wonder about the first pricing. Where they just testing the waters? If you paid it, that would probably be the new price.

 

[Frame Maker]

A story of patience and sharing knowledge. A good bit of positive humanity in your progress!

You're having all the fun! I'm jealous.

You have some good projects of your own. No need to be jealous. Let see some Ducatis

I wonder about the first pricing. Where they just testing the waters? If you paid it, that would probably be the new price.

Ya, it was kinda odd. I've been sending work to the previous company where she worked for many years and always very consistent with pricing. She's been at the new company for a year or so. This is the second time I've used them and had this odd experience. Then to make it more odd, last night I sent a very complex part for a quote and the price quoted this time is unbelievably low. So low I doubt if it covers the material cost. Very weird.

 

[gixxerjeff]

So cool to hear about the mutual feed-back with your buddy Greg.
I am really enjoying learning about your process.
Thanks again Julian for the entertaining and educational thread.

 

[bobl]

So cool to hear about the mutual feed-back with your buddy Greg.
I am really enjoying learning about your process.
Thanks again Julian for the entertaining and educational thread.

Plus 1 !! Always amazed.

 

[Frame Maker]

A big care package from China arrived two days ago. It feels like Christmas...

20210321_181837 by andbike, on Flickr

Except for lots of grubby finger prints, everything looks good! In other news I'm no longer unemployedarty ...and I've taken on three side projects so not sure when the next progress update will happen. Anyway, enjoy the Blingtasticness!


20210321_174341 by andbike, on Flickr