So Barney, my 70 R5, has been kicking around since about 2011 or so. It was pretty rough when i got it but always ran weirdly strong.
tis was when i first got it running way back at the old house.
(https://2strokeworld.net/wp-content/uploads/70-R5/70R5-initial-run_-10-scaled.jpg)
i didnt do much w it for a few yrs, but then after i got divorced i went full into making it a rider. replaced crank seals and all the normal stuff, but never split the cases NOR did i ever pull a cyl head. didn't need to, deepest i went was a clutch replacement. compression was always good so f-it.
the last few yrs, after doing a bunch of slow cosmetic upgrades over the past 10 years, and forks/swingarm bushing, etc, all the maint stuff, the motor was getting noisier and noisier. Not really top end noise but at 27K on the bike and no signs it had ever had the motor out, i planned on a lower end rebuild a few mos ago.
bought a vitos crank, a gasket set, seals, etc, all the normal stuff. its a very early one so maintaining the original cases were important to me.
I pulled the top end down and it was still on a 64mm bore, but had later non dykes oem pistons in it, and they measure perfectly, so , as unusual as it is, i left the top end alone, just cleaned it. ( i was fully prepared to rebuild it... but no need) so at some point somebody had done the top end ( i knew it had been off by the witness marks on the head bolts)
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/70-r5-motor-2025_14.jpg)
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/70-r5-motor-2025_17-2.jpg)
However, the crank shaft had def spread, it was almost 2mm out width wise and was pushing on the outer bearings pretty good, they were roaring when it ran and that's the noise i heard.
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/70-r5-motor-2025_21.jpg)
the vitos cranks are very well built, and there's rumors they come w cheap bearings etc. NOPE.
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/70-r5-motor-2025_46-1.jpg)
so, since its an early motor, there were def some casting difference, quite a bit actually. i wont show most of them but the inside is pretty clear vs a 73 RD350 case. (which i stole the 6 speed out of to put in the r5). the rd was mush more refined a casting. no worries the 73 rd motor i had was already apart as it also had a bad crank.
r5 motor:
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/70-r5-motor-2025_58-2.jpg)
rd motor:
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/70-r5-motor-2025_59.jpg)
cases cleaned at local coin op carwash. used S100 and some brushes. want edo keep original finish, why they weren't blasted.
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/20250207_192506.jpg)
r5 motor w new crank and rd trans (all of it) w new bearings etc
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/20250207_213040.jpg)
frame cleaned and touched up it was SUPER nasty under here.
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/20250208_095853.jpg)
cyls painted etc.
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/20250204_190027.jpg)
and all back together. way, way quieter, smoother, and the 6th gear is admittedly very nice.
(https://2strokeworld.net/wp-content/uploads/70-R5/2025/20250117_173503.jpg)
keep in mind, this is a dead bone stock tuned bike, airbox, lid, etc. the ONLY thing different from stock is a vape cdi, set static to 1.9mm btdc. and a 520 chain conversion from EC from yrs ago. thats it. and its one of my favorite bikes to ride.
100 at the quarter car wash... so that's probably a good half hours time right? lol.
All jokes aside quarter car wash was how I did mine the first time too. But I admittedly got sick of getting water blasted back at me and gave up after 20 minutes and being drenched.
I'll wear my waders next time!
Love it!
:patriot: :patriot:
She's a peach.
Quote from: Striker1423 on March 24, 2025, 09:52:41 PM100 at the quarter car wash... so that's probably a good half hours time right? lol.
S-100 cleaner, not 100 bucks. lol.
That is a really pretty bike and I must say,and I like the look of the R5 just a bit more than the RD with it's paint schemes,colors and polishing more metal bits here and there. I assume that's original paint but the seat looks new and really comfy. Like a more cushy aftermarket cover vs. the original?
One of a few or more things I envy of a lot of you folks living south of the Mason Dixon line and even more toward the midwest then myself being in Ma. is over the years I have noticed whilst window shopping FB marketplace is lots of old motorcycles for sale that I just don't see around New England. Especially in PA. that state seems like a hot bed for vintage two strokes.
I remember going from R5 with chambers to an RD400 with chambers was disappointing. The rd400 for me was harder to tune and had that flat spot I couldn't jet or adjust out. It was a more refined comfortable bike to ride but I liked the R5 better. Had a bud who had a ported R5 with old denco chambers with drum brakes and that thing was unbelievable. He surprised some dude with a old FZR400(new back then) on the los angeles crest hwy canyon and just blew right past him on the turn. I feel that the R5 was one of the best bikes yamaha ever produced.
thanks. that bike actually originated around the great lakes and was found at the barber swap meet from the guy I got it from. the paint is all original, but the tank is an nos one I bought a few yrs ago. had a slight scratch on it but didn't care. the seat was done by my local upholstery guy, dies amazing work. it's def NOT a show bike but it's pretty nice to look at.
I agree, rds are much harder to tune by comparison.
how much difference does piston port vs. reed valve make when tuning?
piston port doesn't have the same reversion issues. so, it's easier. I always found kawasaki triples much easier to tune than rds. but, there are tradeoffs
Looks great, Mark! That's good to hear about the Vito's crankshafts. I've heard some rumors over the past few years that made me doubt their quality.
I put a vitos in the lc hybrid last year. I checked the runout and everything, it was pretty much perfect. so, the rumors are bs these days. maybe 5-10 yrs ago? but.. nope..all good. and keep in mind, I can and have rebuilt my own crankshafts.
Hey, did someone say Barney was here?
(https://i.postimg.cc/Y4Y5qJhw/Screenshot-from-2025-03-26-11-50-56.png) (https://postimg.cc/Y4Y5qJhw)
(https://i.postimg.cc/vgvC5frq/Screenshot-from-2025-03-26-11-52-14.png) (https://postimg.cc/vgvC5frq)
:bacon: