Yamaha SZR 660 conversion to 350 YPVS - ( TZ250 replica )

[evan_calgary]

Thank you both MK and Evan!
Then...

1st - media blasting
2nd - quality welding
3rd - powder coating (satin black)

But I still have to solve the torque bars installation, which I believe fundamental to avoid undesired side effects...

If they want to use sand make sure it is a fine sand. You will have a better final texture to the frame once powder coated. Usually something that large will not fit in the bead blasting booth from my experience. If they are cool with using beads then ignore!

Ensure the powder coater is well aware of the threaded bolt holes that need to be protected form powder otherwise you will have lots of work with taps. Some do this as they should without questions and some will coat hte threads if you don't specifically urge them not to.

[MK]

Here's an example what it may look like :
https://www.millerwelds.com/resources/a ... motorcycle

[Ricino]

Thanks, Evan

The blasting guy uses by default aluminum silicate and will ask him to use fine grain. I’ll protect the threads and the swingarm and front race’s bores during both blasting and painting processes.

Thanks also to MK for the interesting article. Nice food for thought!

[Ricino]

Hello there,

Very slowly yet sort of steady I´m continuing my project.

The welder closed all the scars on the frame. Those huge screws will be substituted with some dome-barrel-socket bolts.

Tinypic sucks... all the images have expired and now I´m using the same pic database as Smoker, which is postimage.org ...Very user-friendly!

[Ricino]

I will also fabricate some new tie-bars, but my next step is to adjust the expansion chambers, slightly re-routing them.

Kenny-TSA made them, they are a precious copy of a pair made for a (4DL) very similar project several years ago, so I assumed some adjustments would be neccesary and that´s what I´m doing now. Cut & bend. Cut & rotate. Once finished I´ll take them to the welder, and will locate the mountings afterwards. Then I´ll put the stingers, their flanges and silencers.

[Yellow and Black RZ]

Looking good. Keep at it.
Hoping to see this one running.

Good luck.

[Ricino]

Thanks Y&B RZ !

Here are some pics after adjusting both chambers' routes. It has implied cutting with a very fine disc, rotating and some sheet metal work to perfectly adjust the cans' borders in order to tig weld. I've been able to very closely observe TSA-Kenny's good work and excellent welding seen in the inside side of the seams.

I'll take the chambers to the welder hopefully soon, although here in Spain we also have some confinement issues (now less severe than a week ago).

Once welded I'll design some mounts and the stingers' routes.
One reason not to do it now is that I need the chambers to be sturdy enough in order to accomplish that further work.

[Ricino]

Slowly yet going...

I'm still dealing with the chambers, and the tie bars at the same time because I'd like tio take the bits to the welder in one move.

So, the new tie bars are pointing to the rear wheel instead of the front wheel. This is because there is a nice sturdy mounting point (as seen in pictures) in the original SZR 660 frame, which used to be a former engine mounting point. I´ve had to cut and bend them. I thought they were solid, but they're made out of 10 x 2 mm. tubing, so, I´ve used some 6 mm. rod that has helped a lot to guide and to connect the separate parts. I´ll finally get some new tubing welded, though (leaving the rod inside)
(Yeah, I know... I know everything looks filthy hahaha! I'll fix that)

Does anyone know what is the function of the protuding cast tube right below the oil drain screw?
I need to cut it in order to finish one of the tie bars.

[Ricino]

I've finally removed the case's casting protusion so I could route the right tie bar.
I´ve curved the rods in a very rudimentary way, that's why they look dented, although they're still strong enough.
I still have to solve some clearance issues on the right tie bar.
They're pointing backwards because there is a strong attachment place in a transversal part of the frame (a former original engine mount)

I´ll complete the rods once I cut a second hand tie bar because it is not being easy to find some 10 x 2 mm tube.

[Questo vecchio rz]

You are doing a fine job

[Ricino]

Thanks, Vecchio. I'm trying to do my best, well aware of my limitations and very grateful to this great forum.

[85RZwade]

Your limitations seem to be few! I think you see possibilities where many of us would see problems, and your bike is going to be interesting and unique in the best way when you're done. Good on ya!

[Smoker]

Enjoying your thread and the work you're doing.

Curious why you're leaving the bolts in the engine mounts? Your welder is good, is there a reason not to weld up the bolt holes?

The tie bars are rubber mounted. Do you have enough clearance for vibration and engine torque movement? Hope that makes sense.

Keep up the nice custom work!

[kpke]

Yeah, that one modified bar looks really close to the nub. I have no idea how much movement there is when full torque is applied to the engine. Can't be too much???

Love this project.

[Ricino]

Enjoying your thread and the work you're doing.

Curious why you're leaving the bolts in the engine mounts? Your welder is good, is there a reason not to weld up the bolt holes?

The tie bars are rubber mounted. Do you have enough clearance for vibration and engine torque movement? Hope that makes sense.

Keep up the nice custom work!

Yeah, that one modified bar looks really close to the nub. I have no idea how much movement there is when full torque is applied to the engine. Can't be too much???

Love this project.

Thank you both for the feedback and compliments!

Yes, I'm going to modify one of the tie bars because there's not enough clearance. I can remember how shaky an engine can be and I clearly could have clearance problems. At some point I will order and replace all silentblocks (engine&rods).

Smoker,
I'm still leaving some of the bolts but yes, some of them will be removed and welded up. But I'm gonna leave the ones at the twin spar frame because in the inside there are blocks made of several plates and I feel they should keep fastened unless the welder could fill the entire hole, which I doubt.... I will substitute those bulky and ugly bolts, though. I´ll look for some domed "socket style" ones.