couldn't resist. rz250

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gman
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couldn't resist. rz250

Post by gman »

G'day race fans. You may or may not have seen this bike listed for sale recently. I went to check it out yesterday and luckly i had the trailer and some cash with me. Yamaha rz250 1xh 1988 model. has a fresh engine that was ported and set up for the track. heres some pictures fresh of the trailer after a wash.
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gman
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Re: couldn't resist. rz250

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took the bike for a ride around the block this afternoon. Motor is very smooth and pulls well. there is a flat spot/stumble around 6 grand and when you go to wot. I've since stripped the carbs and flushed the fuel tank. the bike is running a y boot/k&n filter, variable advanced timing plate set at plus 4 degrees advance and batterie eliminator. the prior owner quoted the main jets at 250 which seemed reasonable but apon stripping the carbs i've found 170 mains. I've noted all carb settings. needle jet-345-p2, needle 4n10 2nd clip from top, pilot 25, main 170, slide 2.0. Does anyone know the factory carb internal parts? I would think the needle, needle jet and slide would be stock. weather or not the main has been drilled i'm not sure. I have allot of main jets and may try a known 250 then go from there.(t edit. found out factory mains are 155/ is that right?) Old mate said he didn't think the lights would get enough power with the battery eliminator capacitor so i will probably put a battery in connect up the lights, buy some indicators, check power valvue operation etc. happy with my purchase though. I like the look of the bike and allot of things have been renewed. Came with reciepts for a new crank shaft, serco porting,pistons, r6 shock, all bearings and seals. just needs a tidy up and it will be ready for the road. Image Image
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OzzyElsie
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Re: couldn't resist. rz250

Post by OzzyElsie »

I did see that on EvilPay and thought it was good buying at $2200 or there about.

Sounds very tasteful, the look not so much, but a little TLC and some fettling it will be a 'keeper' :P
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Re: couldn't resist. rz250

Post by Greasemeup »

The blue ones look just as good and just as iconic as the other colour of RZ you have there for mine. Seems you were very lucky that day :)


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Re: couldn't resist. rz250

Post by JonW »

Nice looking bike for the money, these days that should have been half as much again if not more, especially if it was in Sydney.

The 4N10 and p345s are right for the 250 (fixed) PJ carbs, but I dont remember the jet sizes. They are listed in the parts book with their sizes on the carb page if you can find a copy of that, perhaps ask Xavier who runs rd350lc.net or maybe the local yam dealer can look em up for you as its an Aussie delivered machine?

These are an interesting bike as they are an 87/88 model, which Im not 100% sure if were a full line for Yam Aus as most people say we only had the RZ until 86. The fully faired 86 model was a 'proper' F2 with everything that entailed, but these later bikes were N models, ie had F1 bars, N1 clocks. For those who are amateur historians, we still cant really work out yet if they came delivered with the round light Full Fairing (a kind of F2 model) as well or if that was aftermarket. For now we have to assume it was perhaps a locally sourced dealer option, as only one person (Alex, bobbyd on here) ever said they had seen a plastic version of the round light fairing upper (the F models elsewhere all had rectangular lights), everyone else who had one says they are gf. Interesting mystery, especilaly as there are no brochures for these bikes, but sending us N models would make sense in that in the 80s we were one of the dumping grounds for the less desirable (in other markets) models and perhaps Yam Aus 'modern'ed' them up with a full fairing to make em sell etc. I mean, not many people wanted a non faired bike when everything at the time had a fairing, including the previous year models. Also, they do all appear to have been blue when new too, but single colour choice on bikes isnt new in Aus of course. Always happy to hear from others about these bikes, as little is known.
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Re: couldn't resist. rz250

Post by gman »

Thanks for the comments gents. I hadn't seen this model or colour rz before, least not in the flesh. I call it number 12 or the baby blue one. When talking about the bike with the miss's, she was very supportive, she said "what are you an enthusiast or a collector?" i think i've become an enthusiastic collector. The following pictures show the bike parts that have numbers as well as a shot of the intake port. I can stilll see hone marks on the cylinders. The tank still has it's original stickers all be it faded, 1 is unleaded only the other is about side stand cut of switch or if not fitted a reminder to put it up before selcting a gear.
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Re: couldn't resist. rz250

Post by OzzyElsie »

Painted in the colours of the French Yamaha Race Team.

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I have always liked the colour scheme. It was sold in Australia but only in the last year or so of their sales. Not a lot sold, fairly rare. I think there was a full fairing version as well.

The gold rims look good. :P :wink:

That inlet looks ported - wedged the bridge and smoothed out. How ported are they - just tidied up or........OMG, is that the power brand.
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Re: couldn't resist. rz250

Post by hybrid »

Lozza won't like that knife edge.
I wonder how long ago they were ported. Apparently that's not the preferred method these days.
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Re: couldn't resist. rz250

Post by JonW »

Agreed, they are an old school port job, and very smooth with that polish too. The wavyness of the knife edge and the shinyness of the walls (and what are the pits from?) makes it look more like a home job so thats pretty interesting, I looked up Serco and they didnt seem to offer porting now, worth a call to them perhaps to see if they know what was done? Either way if it works on the road then thats cool. Even if it didnt its not like 1XG cyls are expensive to replace of course LOL.

If you want to make this fly you can add yz85 VF4 reeds (only need to relieve the cyl edges) and I would remove the +4 setting on the stator plate and run a Zeel, adding a blanket amount of advance isnt really ideal. You might get rid of the 6k stumble with those mods, if not add some reed spacers that often cures it. HTH.
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Re: couldn't resist. rz250

Post by gman »

I agree with you john w in regards to the +4 ignition, the old owner said he recconed it picked up allot of power from going the +4. I don't know what exactly has been done with all the ports and transfers and yes lozza wouldn't be happy with a knife edge intake bridge and the polishing is questionable. I've looked back through the reciepts with the bike and there is a reciept from Serco brisbane for 2 rz250 port 2 stroke cylinders $400 dated 19/10/2011. Since a pair set of stock cylinders are the price of paper weights i'll get a pair to keep with the bike. I could put on a set of 350 cylinders but i think i'd like to keep the bike as an original 250. The bike does have tdr carbon reeds and reed spacer blocks.
Today i put the bike back together and went for a few laps of the block. bike starts and idles great. feels rich of idle and pulls good to the middle throttle. 1/2 to Wot the bike dies. I am not familiar with power jet carbs, i removed the carb bowls again and it seems like the outlet from the bottom of the bowl to the pj is blocked (no fuel in clear conection tubes). I've tried clearing the outlet with a guitar e string and compressed air with no joy. Does the outlet unscrew from the bowl?
Another issue is the battery eliminator. I connected the head light harness and the dash, headlight, and tail light work, although the lights are somewhat dull but sometimes go bright. Maybe it's the eliminator or a bad earth.
I can try a battery in the bike, can also try a spare set of 31k 350 carbs, although i would like to get the original set up to work. does anyone use a battery eliminator on there bike?
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Re: couldn't resist. rz250

Post by JonW »

Yes ive heard a few guys say +4 helps the ignition, but the issue is the blanket +4 is too much in some places. If you can stretch to a zeel it wull help for sure.

Agreed a standard set of cyls would be good to have in hand, 350s would be expensive and youd need new reeds and pipes but you could use your 31k carbs of course.

The PJs work where your bike dies, so thats your problem. the PJ helps the main jet with fueling. have you tried carb cleaner and ultrasonic cleaning? the PJs are fixed in your carbs, in the 350 versions you can change them out.

TDR reeds are nice, but VF4s would be better... but cost a packet of course :(

A few of the American/Canadian guys run batt elims, try the rdrx500 forum for more info form them perhaps?
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Re: couldn't resist. rz250

Post by GrahamQLD »

Looks a nice buy!
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Re: couldn't resist. rz250

Post by hybrid »

+4 would have probably helped mid range a fair bit. That is where I picked up most on my LC.
However it won't be helping the top end.
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Re: couldn't resist. rz250

Post by L.B. »

Id have to suggest you fix the handle bars asap....put the locator cap head bolts back in & readjust the switch blocks/grips. Why has he lowered the fork tubes through the triples? Its a road bike....on the road not the track.
I have a 250 N1,I thought it would be enough for me,but the bigger cc got me in the end & here I am wanting alot more lol.
I'd changed the carbs for the non pj type,easier to work with or just go pwk's if your looking at 250 ported & if your looking at another set of 250 barrels look for the 51L as they have a boysen type port deal & from what we can tell are the last development Yamaha did for the RZ250 engine.
As Jon mentioned the VF4 reeds would be nice but man are they exy,I too found the tdr reeds worked well.250 can be alotta fun,but man 350 is even betterer......just sayin.
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Re: couldn't resist. rz250

Post by JonW »

Shush LB! I was keeping the 51Ls a secret ;) :D

I believe Yamaha licenced the technology for only one year (well 2 in Japan) and when they created the 85 RZ250R (debuted in 84 in japan) it had the best of everything you could get for the 250 parallel twin; better pipes that work, boyesen port, pj carb etc. But it was no RGV/TZR and that killed it. They were cutting costs on the model after 85 and just went back to making it a smaller version of the 350. Interestingly the pipe design was good enough to make it onto the 350 86-on, but the port was dropped. I doubt that it didnt work, but rather it was expensive. The same sort of thing happened with the KX / KDX 250. KX has the port, KDX does not. The motors are very similar as you would expect and the port is even 'ghosted' in the casting, but not drilled thru. A bit of time with a dremel and you can have extra ports in a KDX motor and they really fly just like the KX, which was known for its speed back then, tho even the standard KDX was no slouch for a 250 trailie of course. Kawa cited the cost for not adding them to the KDX, no other reason.

Good spot LB! I hadnt noticed the grips/blocks have been slid down the bars, thats mental and potnetially dangerous if there is nothing under them! And, eeek... The caps are not screwed in as you say, and they should be as Yam found the clamps not sufficient on their own, or they would have not made them like that. The knocks you get on the road from pot holes could move those bars as they stand :/ Agree that the forks being run thru the yokes might give you better handling on the track as you say, but for a roadie they will make the bike a bit 'pointy' perhaps? Whats it like to ride gman?
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