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Anyone using Rz350 Wiseco Prolite in the air cooled RD?

I bought a set and modified it (remove the tab) just like we do on the Pro x. They are also made for 0.003" like the air cooled Wiseco.

The modified Prolite is 22% lighter, making it almost as light as the Prox cast piston.

I am doing winter maintenance on my 1977 RD400; fixing a possible head gasket leak and removing carbon deposits.

I don't know if I got lucky or not, but I caught this rod relatively on time, before total destruction anyway. The associated cylinder shows 0.0005" more taper wear than the healthy one, but I guess it may just be coincidental.

The worn side was showing a bit richer on the piston wash and I suspected a possible head gasket leak. EGT was cooler than the good side, but CHT was hotter than the good side, again these maybe coincidental based on timing (points), carb tuning and other variables.

Mileage on the crank assembly is unknown. I'm getting a new crank with Prox rods.

Does a new 64.75mm (2.549") Prox piston measures at exact size 2.549"? Or it is machined to account for piston-to-wall clearance?

I am measuring my used pistons at 2.5465". I'm am still working on my measuring technique so I may be of by +/-0.0005. Measured on a 90 degrees angle to the wrist pin and at 25% of the piston length from the bottom of the skirt.

My understanding is that Wiseco pistons are made to account for piston-to-wall clearance, i.e. piston measuring at 2.545"-2.546".

My cylinders bores are measuring at 2.5505-2.551",  0.0000" out of round, 0.0005" taper.

...for a total of 0.004-0.0045" piston-to-wall clearance.

Unfortunately I didn't measured new when I put it together few years ago, they were apparently machined for 0.0025" piston-to-wall clearance.

Engine was working ok, I'm just doing winter inspection and cleaning the carbon deposits on the pistons.

After 10,000km of riding my RD350/RD400 this summer I decided it was time for a little bit of refinement for the next few years. I always wanted another trail-capable bike ( I used to have a Wr250r), but couldn't find exactly what I was looking for, until Yamaha came out with the unicorn bike; the Tenere 700! I made the big move and bought a brand new 2021 Tenere. From all the reviews I read and watched my expectations were quite high, after couple thousand kilometers I can testify the bike is the real deal, it is amazing on and off road.

Because of the covid situation I had the privilege of riding my RD motorcycles quite a lot this year. I usually insure 3 bikes per season and put approximately 1500km on each of them. This year I insured 4 bikes, put over 5000km on my Daytona Special, and another 5000km split between my 73, 77 and my other 79. I had the pleasure of burning gallons of 2t oil.

The bikes were all reliable, I always made it home. The only problems I encountered are the following; One needle valve got stuck open, but I made it to the gas station on time after the classic hit on the side of the carburetor, problem solved. The other problem was that one oil line disconnected from the carburetor while riding. I don't know how long I drove it like that, but I would say 30-45 minutes at speed ranging between 70-100km/h before I stopped for gas and noticed the side of the bike was covered in 2t oil. I'm lucky I didn't slide as the rear tire was wet. I reconnected the oil line and made it home. That engine was a recent build, when I later opened the engine for inspection there was absolutely no sign of wear, still look new. Thanks to modern oil technology, pumping at a generous average of 32:1.

All my bikes have standard $20 RK530 chain. On my Daytona Special, the chain required few adjustments and has "stretched" about 1% in 5000km. Not bad considering I kept the chain somewhat dry to avoid the mess.

Anybody else put more than usual mileage this season?

Is it a myth than when you open a good working engine you should find a puddle of 2 stroke oil in the crankcase.

I just opened a rd400 and the components are well coated with thick 2 stroke oil, but there is no puddle in the bottom.

The bike has autolube and average 32:1 to 40:1 Oil ratio depending on how fast I ride.

I put 3000km of street riding on one of my rd400 (wiseco pistons), ring gap went from .012" to .018 for the top ones and from .014 to .020 for the bottom ones.

It that wear normal?

Compression was and still is 120psi.

Here is my setup for my canadian RD400 Daytona Special (street bike):

Stock porting 2R9 cylinders
65mm Wiseco pistons, 120psi cold (after break in)
OEM CDi 2.0mm (OEM recommended)
B9ES (OEM recommended)
Foam pod air filters
OEM exhaust

VM28 carburetors
170 MJ

Mid range is running very good, but it started detonating around 7000 rpm at wide open throttle in higher gears.

At 2.0 timing my EGT were the following in 4 th gear w/o:

4000-5000 rpm: 800-950f
5000-5500 rpm: 950-1100f
5500-6000 rpm: 1100-1150f
6000-7000 rpm: 1150-1200f
7000-8000 rpm: 1200-1250f

I lowered the timing to 1.9mm and now the detonation is intermittent passed 7000rpm.
The EGT are now running 50-100f higher passed 6500rpm which confirms It now detonates less (right?), but dangerously getting 1350f at 8000rpm.

Spark plugs don't show sign of detonation.

I'm a bit puzzled at this point.

To play it safe I would have to go to 1.8mm and 175 main, but I'm afraid I'll loose power between 5000-7000 rpm, where it runs very good.

Is there a way to increase fuel only in the high rpm? Bigger carburetors?
Is intermittent audible detonation an absolutely no-go?

I found that part in my stash and I want to share what a failure of the mikuni oil pump could look like. I think the pump ran without oil and shewed the plunger cam. I couldn't find the plunger, but I'm sure it was not pretty.

I had a Canadian Daytona head that was quite damaged on one side. Last year I posted a picture of it on the former board and another member offered me for sale a Canadian Daytona head that was damaged, but on the other side. The two heads could be cut and the good sides used. So I proceeded to cut the two heads and painted them orange (leftover paint from a snowmobile project). It looks pretty cool.

It is stamped 59 on the body and stamped G7 on the lever. I would believe it was for a single cylinder, maybe AMF Harley-Davidson, Can Am MX ???

I found a set of plastic reeds in my stash. I remember reading they would be from a Daytona Special. I would like to know if they are any better than the metal/rubber coated ones. The plastic ones look cheap, it makes me think they were just trying to save money.