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Been on there for years. Way over priced. If you are looking, one comes up stateside once every other year on the TA125 facebook page.

  Someone who was a Kawasaki H1R mechanic recently brought to my attention, that the black oem japanese base gasket material is designed to stick to the aluminum. With thin sealing area at the block, they struggled with the base gaskets shifting, causing air leaks and seizures. When they didnt grease them, they didnt shift. Ive noticed it also takes a certain time or amount of heat to bake them to the aluminum. If you take an engine apart soon after without hard running, they often wont be stuck.

That being said, i had always put a film of grease on my base gaskets, but now recently i use Vibra-Tite 73250. Its a non hardening tacky gasket sealer. I deal with yamahas, and have never experienced a shift.

  I guess if you have a thin sealing area of your transfer ducts, using grease or sealant is not the answer. Also depends on the material your gasket is made from.

Very nice and clean. Good combination of parts to make a fast bike.

Looks awesome.  Some good work on those rearset mounts as well.  Have any spare upper rearset bars made?  I need a couple bent for a similar rep.  This is fairly close to the TA which I am guessing you modelled off!  Very nice work.

Thank you. Yes its a direct TA knockoff. Unfortunately i dont have any other spare tubes made, I borrowed a friends tool to do them. Although im sure you could get away making them with an oxy/acy torch, the bend isnt that tight.

Some good ones. Gary Cowan on a TZ250 vs RG500 and RC30
https://youtu.be/qQGAOhY8PWo

Brian Reid TZ250 IOM
https://youtu.be/SuQEfT3kLjA

Bike racing in the 70s (mix of 2 strokes with a good amount of Jarno Saarinen footage)
https://youtu.be/kPLjZut0ero

That is fantastic. Some fine engineering solutions going on under that hood: the shift linkage, clutch cable, exhausts, drive shaft off the countershaft. Love the high tension wires! The car itself is really cool, too...but in noticing the "choke" plunger, I wonder how they start it? Too dark down by the kickstart shaft to see what ingenious mechanism is utilized. Maybe they park it on a hill  ;D
Wade

RD200E. Electric start. Agreed on the mechanical solutions, done very well.

Gas tank stuff

I havent been on this forum in 4 years, so i decided to share one of my builds since then.

  The engine is a Ls2 100 bottom end, with RD125 top end. Its heavily ported and has durations similar to a TA125. Crank currently being built to TA specs by Gary Braun. Power is from 9k-12.5k. The pipes ive built to match my porting, silencers are made entirely of aluminum. Vm26 carbs, rd350 boots, stock cages opened up with fiber reeds, little boost bottle. Spark provided by an Electrexworld CDI.

  The frame is actually a RD200, because i had a donor roller in my shed. The modifications to make it like a TA frame are as follows. De-lug, bronze bush swingarm pivot from 15mm to 12mm, use RD125 swingarm, add rearset foot brackets, cut out and make upper shock mounts narrower (never fun). Weld in spacers for engine mounts, inner fender tabs, rear cable holders, coil mounts, and tach/fairing mounts if you choose. Vapor honed hubs, laced up with Akront 1.60 rims.

  Gas tank and seat i made fron .063" 3003 aluminum, tig welded (next tank i will learn oxy/acy on 1001 alum). The gas cap is a repop, but the mounting base and breather cap i made by hand. The yamaha decals are TA125 replicas. I read about a guy waiting 15 years to get a chance to buy a real TA tank, so i just had to make my own.

  I spent 3 years of parts gathering and researching before i built anything. It was one year of consistent building on nights and weekends. I have done some testing on rural roads, first time out i was having trouble pulling in 5th with 15/35 sprockets. I went to 13/35 and it screamed. Gary has pressed on a shorter 5th i found, but im currently in the early stages of modifying a YFS200 six speed into it to get my top speed back. I plan to cast my own 100cc cylinders for Ahrma racing, so that is whats next. I will probably make a new frame, Van Tech style for once its a race machine. The TA seating position is extremely aft.
Dont see a lot of people messing with the little twins, so information is typically direct to anyone who has a TA, or the RDX racers in the UK, if you have any questions regarding them im happy to help.
  Cheers, Sean from Detroit.