I have to agree with the 125 thing although I never really thought about it as has been discussed, there are a lot of carry over bits from 250s to the open class bikes like say the seats and tanks of a TM250/400 etc.
Having been at this for a few years , got the first of my VMX bikes in 88 and been restoring them since, I have to say the the YZ250a that I have been doing to 3 years for Steve Gall is no question / hands down the hardest and Ive had some hard ones to do.
With the RN400L - I had all the bits and as rare as they are they were all there and either new or good, the RH250 as well. The KXs were all good to start with even though difficult for parts my experience sees them more available than YZA stuff. I guess though my real point is that the resto is as hard as the bike you have and the state its in. Two of my KXs have never been apart and except for a look inside are original all the way so even with rare bikes restos can be easy if the bike has been well maintained and is complete.
As for the YZ250A, oh how I would love to give it back and get it out of my life, its just so frustrating and slow and the search for the correct bits is soooo hard. Its going to be a garage queen and the cables need to be grey, the tank straps need to be the right ones, the nuts, bolts, washers all need to be the correct stuff!
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