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

[(F5)]

I run a tie bar sideways on my 496 as well. Engine tilted quite a bit on the dyno dialing in 100hp. I now understand that the engine rubber mounts can be replaced and do get sloppy, a job for next time.

Looks great. Those long thin front drops do make me a little concerned given the twisting possible (see above). My Honda RS125 with shorter bars had large box section. Maybe brace with a right angle to make T section?

[JonW]

I run a tie bar sideways on my 496 as well. Engine tilted quite a bit on the dyno dialing in 100hp.

Interesting. Did you put a boss on a frame rail to tie it to? Any pics?

[Ricino]

Looks great. Those long thin front drops do make me a little concerned given the twisting possible (see above). Maybe brace with a right angle to make T section?

Thanks a lot for the valuable input! Those thin rods have been of great help in order to guide the new routing and they're still not welded. I'll complete the rods with some tube, then will weld.

I've thought several times about that T section... Do you mean to weld both tie bars together in an H manner? Or just reinforce each rod? I am worried because I feel that both tie bars should move freely and independent of each other. What do you think about this?

[(F5)]

Actually I was meaning the ally frame spar drops to the front engine mount. They could live with some more east/west stiffness I'd venture. Maybe Google as many frames as you can to copy.

My side tiebar is to a sidestand mount which is bolt on on my braced RG250 frame, so not very comparable now I think of it, as it has a lower frame rail to hang off and sidestand forward of gear lever. Not sure what to suggest.

I would try get a long lever somewhere real safe and try rock the engine to assess the condition of the engine rubbers. Someone here, I'm going to guess mk, will know where to source new ones. I read about Stan Stephens replacing them in a CMM magazine. With decent rubbers and stiff front mount you shouldn't need a side tiebar.

[Ricino]

Thank you sooo much F5, now I fully understand what you mean and I think you're so right about east-west stiffness. I'll do some research and figure out something in order to strengthen those plates.
( this issue was mentioned... #61 through #65 posts ......now I've fully eliminated my wishful thinking and I'm more science oriented hahaha)

[Mograt]

I'm loving this project. I currently have SZR660 that I'm toying with the idea of turning it into a 2 stroke. Your doing great, keep going I want to see the end

[kobra]

Looking good, keep it up. I love the hand work and willingness to try things.

[Ricino]

Hello again,

Thank you for the kind words.
Going very slowly, but willing to accomplish a few things along the summer, like reinforcing the engine mount plates to deal with east-west forces, as suggested by many of you (specially forum member F5).
As suggested, I´ve been searching in some old GP paper magazines (1989 GP World Championship) and have found some nice solutions. I'll definitely reinforce the plates in a box-section manner, as shown in the pics below.

Gazzaniga 125


Honda 125


Cagiva 500


I now see it as an easy job, just a matter of patience and precision hand cutting, bending and welding (the last done by a very competent professional)

[jerele]

Hello Ricino, I lost your phone number.
I don't know how you carry your project.
I just encourage you to keep going. It will take a lot of work to fit the 4DP fairing, but it is possible, although I have not finished fitting it.
My project already sounds and fumes.
Saludos.

[Ricino]

Hello Ricino, I lost your phone number.
I don't know how you carry your project.
I just encourage you to keep going. It will take a lot of work to fit the 4DP fairing, but it is possible, although I have not finished fitting it.
My project already sounds and fumes.
Saludos.

Thanks! The project is going very slowly, if going... five children already is a very demanding task. I will send you a private message with my phone number...

Congratulations for your keen project, looks very good.
Is there any other forum where we could see your project evolution?

Thanks again,
Patricio

[jerele]

IMG_20221107_205234.jpg (241.81 KiB) Viewed 1412 times

Terminada.Espero estrenarla este próximo sábado.Solo he publicado fotos aquí.
Saludos a todos

[jerele]

Finished. I hope to release it this coming Saturday. I have only published photos here.
Greetings to all.

[kpke]

Stunning and beautiful work there.

[(F5)]

Best use of a 660 ever.

[jerele]

Four years to make it. We tried it this Saturday. A devil dressed in white. HPI rotor, TM 28 SS and a copy of Jolly Moto.
Next up: TL 1000R chassis, VFR swingarm, and 350 YPVS engine.
Several years of work.
Greetings.