RZ250R conversion project to be an RZ350R
Moderator: rztom
RZ250R conversion project to be an RZ350R
So I managed to get a good priced RZ250R to someone whose trying to rip me off saying its an RD/RZ350R and wanting me to pay high fortune for it, so I was personally checking the bike further as the basic and checked the Frame chassis and engine number and immediately find the starting numbers with 29L stamped did some searching on the internet and some asking to some friends who know more 'bout Yamaha 2 strokes and was confirmed that the bike that is being sold to me is indeed an RZ250R and not an RD350 that is being advertised by the owner himself. Long story short we both agree on inking the deal that is agreeable in both ends, got me an RZ250R and he got his money, both of us return to our caves with a printed smile on our face.
So I wanted to know what will be the necessary parts needed for the conversion to make it an RD/RZ350 itself and what are the parts I can reuse or need to replace?
So I wanted to know what will be the necessary parts needed for the conversion to make it an RD/RZ350 itself and what are the parts I can reuse or need to replace?
Re: RZ250R conversion project to be an RZ350R
I believe you need the pistons, cylinders, head and oil pump. Rejet the carbs. I’m not 100% on the exhausts.
1985 RZv500
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1984 GPZ750 Turbo
1989 VFR750R RC30
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1984 GPZ750 Turbo
1989 VFR750R RC30
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Re: RZ250R conversion project to be an RZ350R
Follow Jon's RZ250 conversion here viewtopic.php?f=5&t=4650
From Jon's website, this is the conversion parts list. http://2smoked.com/Yamaha_1985_RZ250_to ... rsion.html
Contact him if you have questions. I'm sure he'd be happy to offer advice.
From Jon's website, this is the conversion parts list. http://2smoked.com/Yamaha_1985_RZ250_to ... rsion.html
Contact him if you have questions. I'm sure he'd be happy to offer advice.
Re: RZ250R conversion project to be an RZ350R
There's a couple of alternatives to 350 cylinders.
1) Why not ride it as a 250 first? Give it a try and you may like it.
2) Banshee cylinders will fit, but stock banshees will have about equal performance to the 250 YPVS.
You could get a cheap set from Alibaba and port them.
https://a.aliexpress.com/_mP9yGAX
You'll need to fabricate an adapter for the pipes as the banshee has a different flange.
3) Any aftermarket banshee stuff will fit, too.
The Athena kit is the lowest price per hp.
https://www.athena.eu/en-us/big-bore-cy ... P20737.htm
You can get into the 80'ish hp with these.
1) Why not ride it as a 250 first? Give it a try and you may like it.
2) Banshee cylinders will fit, but stock banshees will have about equal performance to the 250 YPVS.
You could get a cheap set from Alibaba and port them.
https://a.aliexpress.com/_mP9yGAX
You'll need to fabricate an adapter for the pipes as the banshee has a different flange.
3) Any aftermarket banshee stuff will fit, too.
The Athena kit is the lowest price per hp.
https://www.athena.eu/en-us/big-bore-cy ... P20737.htm
You can get into the 80'ish hp with these.
Bye
Martin
Martin
Re: RZ250R conversion project to be an RZ350R
might be a good Idea but since I wanted to up bore it up to 350cc is a better Idea :)MK wrote: ↑Wed Mar 24, 2021 5:36 pm There's a couple of alternatives to 350 cylinders.
1) Why not ride it as a 250 first? Give it a try and you may like it.
2) Banshee cylinders will fit, but stock banshees will have about equal performance to the 250 YPVS.
You could get a cheap set from Alibaba and port them.
https://a.aliexpress.com/_mP9yGAX
You'll need to fabricate an adapter for the pipes as the banshee has a different flange.
3) Any aftermarket banshee stuff will fit, too.
The Athena kit is the lowest price per hp.
https://www.athena.eu/en-us/big-bore-cy ... P20737.htm
You can get into the 80'ish hp with these.
Re: RZ250R conversion project to be an RZ350R
Does amuse me that people think a 250 is some kind of rip off, probably these days an actual 250 is probably rarer lol
Ive no idea where the OP lives but if its a JDM RZ250R its probably a 51L cylindered bike. Feel free when you junk those cylinders to send them boring ole paperweights to me :)
The 51L has an extra (boysen) port that no other RD/RZ cylinder has and pipes/CDI/Carbs to match. it makes good power and revs for days as the engine is actually designed round the 250 size, not 350. pics of those ports on my 251LC build.
I agree with Martin, why not ride it as a 250 and see what you think?
The RZR also is full faired 1985 bike, if you live in the USA it would be rare cos of that by itself. In Canada the fact its a 250 makes it super rare. If youre in the UK, same thing. If youre in Aus then we had more 250s than 350s in 85 and ours are not 29L, so yours is an import. All that said, I bet you tell us youre in NZ... haha.
EDITED: Ive seen you are in the the Phillipines. Cool. Ive no real idea what bikes or the spread of them for your market, but i reckon this bike is an import. We need pics...
I also wrote a big bore primer on my site for those wanting to go for bigger cyls. Its all fits on the same 250 bottom end of course.
My website is now in limbo, the site builder software died last year and is long not supported and it corrupted the local files. I then stopped paying the bill but the hosting company never deleted it. Some bits no longer work which is fine, but the info is still useful Ive been told so Ive made no efforts to remove it.
Ive no idea where the OP lives but if its a JDM RZ250R its probably a 51L cylindered bike. Feel free when you junk those cylinders to send them boring ole paperweights to me :)
The 51L has an extra (boysen) port that no other RD/RZ cylinder has and pipes/CDI/Carbs to match. it makes good power and revs for days as the engine is actually designed round the 250 size, not 350. pics of those ports on my 251LC build.
I agree with Martin, why not ride it as a 250 and see what you think?
The RZR also is full faired 1985 bike, if you live in the USA it would be rare cos of that by itself. In Canada the fact its a 250 makes it super rare. If youre in the UK, same thing. If youre in Aus then we had more 250s than 350s in 85 and ours are not 29L, so yours is an import. All that said, I bet you tell us youre in NZ... haha.
EDITED: Ive seen you are in the the Phillipines. Cool. Ive no real idea what bikes or the spread of them for your market, but i reckon this bike is an import. We need pics...
I also wrote a big bore primer on my site for those wanting to go for bigger cyls. Its all fits on the same 250 bottom end of course.
My website is now in limbo, the site builder software died last year and is long not supported and it corrupted the local files. I then stopped paying the bill but the hosting company never deleted it. Some bits no longer work which is fine, but the info is still useful Ive been told so Ive made no efforts to remove it.
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid
Like Watches? www.PloProf.com & www.DeskDivers.com
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid
Like Watches? www.PloProf.com & www.DeskDivers.com
Re: RZ250R conversion project to be an RZ350R
Martin, do you know anyone that has used those cheap banshee kits?MK wrote: ↑Wed Mar 24, 2021 5:36 pm
2) Banshee cylinders will fit, but stock banshees will have about equal performance to the 250 YPVS.
You could get a cheap set from Alibaba and port them.
https://a.aliexpress.com/_mP9yGAX
You'll need to fabricate an adapter for the pipes as the banshee has a different flange.
There's a YouTube porting guy that says they're okay but not surprisingly it can be a bit of a crapshoot. Sort of tossing the dice that you get parts that are decent quality. Just curious.
Ken's Garage
https://www.youtube.com/c/KensGarage1
https://www.youtube.com/c/KensGarage1
Re: RZ250R conversion project to be an RZ350R
kpke wrote: ↑Thu Mar 25, 2021 10:27 amMartin, do you know anyone that has used those cheap banshee kits?MK wrote: ↑Wed Mar 24, 2021 5:36 pm
2) Banshee cylinders will fit, but stock banshees will have about equal performance to the 250 YPVS.
You could get a cheap set from Alibaba and port them.
https://a.aliexpress.com/_mP9yGAX
You'll need to fabricate an adapter for the pipes as the banshee has a different flange.
There's a YouTube porting guy that says they're okay but not surprisingly it can be a bit of a crapshoot. Sort of tossing the dice that you get parts that are decent quality. Just curious.
Kevin Herr uses them on his Banshees Ken, Reckons the cylinders are great, pistons are junk though, He tunes the crap out of them for alcohol motors and dune racers and drag motors with long rod conversions and never had a prob with them.
1985 RZv500
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1984 GPZ750 Turbo
1989 VFR750R RC30
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1984 GPZ750 Turbo
1989 VFR750R RC30
Re: RZ250R conversion project to be an RZ350R
Phantom, sorry to jack your thread.
Paul, that's who I was talking about. I've watched several of his videos
I would still like to hear if Martin has any experience with these cheap banshee parts.
Paul, that's who I was talking about. I've watched several of his videos
I would still like to hear if Martin has any experience with these cheap banshee parts.
Ken's Garage
https://www.youtube.com/c/KensGarage1
https://www.youtube.com/c/KensGarage1
Re: RZ250R conversion project to be an RZ350R
Yes, I recently spoke to a German Banshee guy who confirmed that the cylinders were not too bad but need to be ported / altered for performance.
Definitely a good bang for the buck relation.
Bye
Martin
Martin
Re: RZ250R conversion project to be an RZ350R
Thanks Martin. Good to hear. I have a 421 build coming up but I doubt I will take that chance.
Ken's Garage
https://www.youtube.com/c/KensGarage1
https://www.youtube.com/c/KensGarage1
Re: RZ250R conversion project to be an RZ350R
Compared to ported stock banshee cylinders, the 421 kits (either Athena or CPI) would be the easier & better choice as they have auxiliary exhaust ports that the stock ones lack.
(Note that for 421 you need a plus 4 crank in addition)
Cost wise the Alibaba kits are cheap as chips. That's why I suggested them to enhance a 250 engine with a low budget.
(Note that for 421 you need a plus 4 crank in addition)
Cost wise the Alibaba kits are cheap as chips. That's why I suggested them to enhance a 250 engine with a low budget.
Bye
Martin
Martin