Best year of USA spec RD350?

[RDnuTZ]

I always assumed the 1975 RD350 was the most technologically advanced and peak of development before RD400 introduced. Maybe I was just biased by how much I like the Orange/Black color scheme I do know stock main jets are smaller on the 1975 and assumed it was forced to run leaner due to USA smog BS or something- but don't know if Yamaha did that with performance in mind?

Sometime ago I was told by a former local (in SoCal) Yamaha Service Manager I knew through VMX racing that the 1974 RD350 was actually the best of the 3 years performance wise stock. Any verifiable truth behind his opinion? If true what are the differences that make the 1974 superior?

[m in sc]

they are technically all the same except in 75 they went to a baffled air filter, different jetting, and high top carbs. TBH, the 73/74 IMHO because of that open filter was better, technically. &4 saw the introduction fo the high top carbs but they didn't perform any different. and, IMHO, the 73 was prettier because of metal tank badges and side cover badges. But, all in all all 3 years are basically the same. 

[RDnuTZ]

any possibility of difference in clutch in 1974? I think I remember (no guarantee there!) the guy told me that was beefier when I pushed him to detail reasons the 74 was "best".

I have a 1973 RD250 Blue w/ White tank stripes and badges that is totally stock that just might get pushed to the front of the project line when everything finally comes home from storage this Summer  I'm basically starting over on all this stuff after diving into VMX full time 20 years ago. The 250 is the simplest of the bikes I have and will be training project trying to re-acquire all the necessary skills before moving on into 1 of my 74 350s and possibly tackle the 1KT TZR250R- unless I decide to sell it.

[m in sc]

i forgot that point and you are correct!. later ones had a 7 disc, whereas early ones had a 6 disc. even a  6 dic setup is ok using fz1000 plates though.

[RDnuTZ]

np. I'm sure you've forgotten more than I ever knew on these bikes 

[m in sc]

i have no other hobbies.     

[dgorms]

Mark, what about chasing donuts! That's a hobby.

[Kawtriplefreak]

I have no other hobbies either and 75 is the best year  

[RDnuTZ]

I had to sell my 1975s years ago while thinning the herd for major relocation. I do however still have 2 1974s and a nice set of Orange bodywork I kept that will go on 1 of the 1974s once I get around to building it. I might have just stumbled into a best of both year's combos for that project 

[m in sc]

   = lifestyle choices.

[85RZwade]

I'm with Tim on this one  '75!

[rodneya]

73 with stock paint looks the best in my opinion.
Unfortunately my 73 does not have stock bodywork after a crash back in 73.

Did the 75 model not get heads with a different fin layout around the inside bolts?

[m in sc]

i think that also changed mid 74, the single fin vs split fin. IMHO unless you are cutting the head, a bunch, doesn't matter performance wise.   

[Hawaii-Mike]

I'm the opposite in terms of paint colors.  I think the '75 Portugese Orange is the best looking.  However, I had a '74 about 40 years ago and a few years ago I picked up another '74 project (some day I'll work on it).  So I'm fond of the purple color too.

[Brad-Man]

I think that the '73 RD350 left stock is simply classic looking.  I have a '74 survivor and a '75 ground up project that will get the best of everything only with a 400 engine as the basis.  I think the '75 is the best looking.