I am a young teenager use to rebuild these many many many years ago, The pistons on the shelf looks like bike was running either way too Rich or far too much 2 stroke oil either the oil pump was pumping too much 2 stroke oil, Strangely enough yamaha rd125 and rd200 including the DX models twins were temperamental , Hence why yamaha for costs and more reliable went for the rd125 LC single, I was not a fan of them, The twins especially if you have a good set of expansion chambers sounds beautiful and feels like your doing 150mph but you glance at speedo lol and around 75mph, I had the rd250 and 400 dx versions also but I always thought that they were a heavy heavy bike, Hence alot of road racers would do this, Rd125 or rd125 dx but put in a rd200/ rd200 dx engine, then port and polish, change the reeds and all.of a sudden you'd have a rd125 with rd200 engine in and tuned that would stay side by side with a rd250, One of my 1st legal bikes when sixteen years old in England was a yamaha RD50 dx black and red, Bored out and tuned to the max , it would beat all.of the 100cc bikes , Unfortunately it would melt a piston every 3 months lol, But I am currently doing a yamaha rd125 dx with a rd200 dx engine, Carburetors in the UK 🇬🇧, you can't find any and if you do see the odd one it will be expensive. Currently I am using suzuki gt185 Carburetors with rubber Reed blocks connecters and so far seems ok, I managed to find a really good clean complete matching suzuki gt185 Carburetors £40 the pair, As opposed to rd125 twin Carburetors £300 if you can find them The suzuki gt185 Carburetors are same make and model of Carburetor , Great video
Thanks! I also had to find carbs, i bought a pair of rusted ones from salvage yard (ebay listing). I used the good parts from two different pairs to make one working pair. Also the exhuast was clogged, points knackered and all the rest haha. After the work was done this bike runs like new. Also i run premix with castor oil although im not sure it was entirely me that made those pistons look so bad.
@@RDEnduro Wouldn't you be better running some quality 2 stroke oil , maybe synthetic ? caster oil is only good for couple of days premixed (found out the hard way ) . Running on Castor oil premix is likely why your rings are gummed up , not really a good oil for road use , we even ditched castor oil (Castrol R ) for synthetic on race bikes in late 70's
Pretty typical wear of a bike that age, seen as she's stripped see what performance pistons like wiseco or proxy ect also you can clean up and smooth the ports on the cylinders to get those extra bits of power but yeah you was lucky with that stuck ring, eitherway she's gonna be great once back together and eating up those miles again 👌👍
I'm going to try to do the cylinder bore myself. I've been reading up on how and Im hoping the cylinder is round as that is an important part. Even "small engine" shops here won't touch this or don't offer the service. But if you watch enough Dale Sweger videos you start to feel confident
I got my RD125 in non-working order
entire cylinders are missing, you are lucky one there.
I am a young teenager use to rebuild these many many many years ago,
The pistons on the shelf looks like bike was running either way too Rich or far too much 2 stroke oil either the oil pump was pumping too much 2 stroke oil,
Strangely enough yamaha rd125 and rd200 including the DX models twins were temperamental ,
Hence why yamaha for costs and more reliable went for the rd125 LC single, I was not a fan of them,
The twins especially if you have a good set of expansion chambers sounds beautiful and feels like your doing 150mph but you glance at speedo lol and around 75mph,
I had the rd250 and 400 dx versions also but I always thought that they were a heavy heavy bike,
Hence alot of road racers would do this,
Rd125 or rd125 dx but put in a rd200/ rd200 dx engine, then port and polish, change the reeds and all.of a sudden you'd have a rd125 with rd200 engine in and tuned that would stay side by side with a rd250,
One of my 1st legal bikes when sixteen years old in England was a yamaha RD50 dx black and red,
Bored out and tuned to the max , it would beat all.of the 100cc bikes ,
Unfortunately it would melt a piston every 3 months lol,
But I am currently doing a yamaha rd125 dx with a rd200 dx engine,
Carburetors in the UK 🇬🇧, you can't find any and if you do see the odd one it will be expensive.
Currently I am using suzuki gt185 Carburetors with rubber Reed blocks connecters and so far seems ok,
I managed to find a really good clean complete matching suzuki gt185 Carburetors £40 the pair,
As opposed to rd125 twin Carburetors £300 if you can find them
The suzuki gt185 Carburetors are same make and model of Carburetor ,
Great video
Thanks! I also had to find carbs, i bought a pair of rusted ones from salvage yard (ebay listing). I used the good parts from two different pairs to make one working pair. Also the exhuast was clogged, points knackered and all the rest haha. After the work was done this bike runs like new. Also i run premix with castor oil although im not sure it was entirely me that made those pistons look so bad.
@@RDEnduro Wouldn't you be better running some quality 2 stroke oil , maybe synthetic ? caster oil is only good for couple of days premixed (found out the hard way ) . Running on Castor oil premix is likely why your rings are gummed up , not really a good oil for road use , we even ditched castor oil (Castrol R ) for synthetic on race bikes in late 70's
Pretty typical wear of a bike that age, seen as she's stripped see what performance pistons like wiseco or proxy ect also you can clean up and smooth the ports on the cylinders to get those extra bits of power but yeah you was lucky with that stuck ring, eitherway she's gonna be great once back together and eating up those miles again 👌👍
I'm going to try to do the cylinder bore myself. I've been reading up on how and Im hoping the cylinder is round as that is an important part. Even "small engine" shops here won't touch this or don't offer the service. But if you watch enough Dale Sweger videos you start to feel confident
Babaaboey