Project Dave Moss CBR250RR MC22 racing in California

Would like the first time I go to Pi is to race be kinda cool lol

 

Thanks Blair (and others).

I want to go with Dave Moss and whatever he's bringing. I am not sure if I will be able to ride.


Mike Norman
G-Force Racing Development
Www.mngforce.com
Sent from my iPhone using Tapatalk

 

hows the 22 coming along mate?? dying for some updates on this little rocket

 

hmm thats weird I wonder how I never noticed this thread. While I was doing heaps of research about suspension for the mc22 some input on what Dave already knew would have been helpful.

 

I've been pretty busy lately but plan to create a photo library of the build with HP graphs. The engine came in just under 50hp and Dave finished 2nd at the first race by a hair. The next race is this weekend so I will post afterwards


Mike Norman
G-Force Racing Development
Www.mngforce.com
Sent from my iPhone using Tapatalk

 

The dropbox link was taking me the login of a microsoft exchange server - here is the correct link
https://www.dropbox.com/sh/x1m7hzedjmceysg/AACtUSSb5MLZDe8Hbr3DoJFQa?dl=0

The images showing the material removed from the upper cylinder near the valves are interesting, is this to reduce valve shrouding by the cylinder wall?
https://www.dropbox.com/sh/x1m7hzedjmceysg/AACtUSSb5MLZDe8Hbr3DoJFQa?dl=0&preview=DSC03102.JPG

Lots of questions on pistons, not for an MC22 however, I'd be interested to know any details regarding the possibility of doing 53-54mm pistons suitable for an overbored and re-sleeved FZR250

 

Just reading about that blowby, I would think that blue smoke on decel is oil getting sucked past the exhaust valve stem seals and burning in the headers, rather than worn rings leading to it. If it's the stem seals you will also get blue smoke that eventually clears from a stone cold start.

Does the engine consume oil? That usually means oil control and compression rings are toast. If you get the head off, have a close look at the valves and plugs. The plugs, exhaust valve stems in the ports (below the guides, intake ones will be clean due to fuel washing over them), valve faces, pistons & combustion chamber should all be a consistent light brown colour if everything is in order.

These pics below are just from google but will give you an idea of what goes on when. It's just like reading plugs for the most part.

Healthy (except for leftmost, looks like bent valves not seating there):



Small quantity of oil burning (white ash on exhaust valves) on 2 & 3, and serious fouling of 1 due to a larger quantity of oil (worn out rings letting lots of oil past), or just running too rich



Worn rings leading to burning oil in the mixture, then contaminating the ring grooves and making the problem worse.




If you are still going with high comp pistons you should get the stem seals replaced, valves & seats re-cut (or new chinese valves, maybe even oversized ones if you're really chasing higher power), new valve springs, and after that re-do the valve clearance. By going high comp, big bore, big valves, you reduce service life, but your engine builder/tuning bloke will know all of this, and it's racing anyway

Love the work thats already been done! 5HP is a big improvement when you're starting with 40/45HP. Keen to see what more can be done!

 

Hi Ruckusman:

Those "Eyebrows" as I call them are exactly that, to minimize the shrouding of the edge of the valve as it passes by the edge of the cylinder. As much as I would like to take credit for that...that's how they come from Honda.

Mike Norman
G-Force Engine Development
www.mngforce.com
There is no such thing as "Too Fast"

 

Hi all:

I really enjoyed building Dave's engine, and there seems to be some interest from others about both OEM replacement parts and High Performance parts. I have just worked out an arrangement with Daido Metal - who happens to be the original manufacturer of all the OE bearings for practically every Japanese engine manufacturer, +Ducati and many more - to get bearings made for engines that are NLA from the OEM. I am working on a piston ring source this week. Please let me know who has interest in rings and bearings. I am happy to answer questions for anyone who asks.

I am also very eager to make some very high performance pistons for these little gems of bikes. The pistons would be a very miniature version of these pistons that, with the amazing help from Cosworth, was able to get for our NC-30/NC-35s. https://www.dropbox.com/sh/fdhg2fey00nox1z/AABf5v9GFxXZigXELd3YIjY2a?dl=0

They will be lighter, stronger and add a decent amount more power. Our rules permit +1mm over the class displacement. So, I am looking at making them for +1mm over 250cc, and if there is enough interest, +1mm over 300cc. Our Racing Sanction has both classes. The pistons may be from Cosworth, or from another exceptional brand from Austria. Since there is a lot involved in the pistons, I need to know very soon who might be interested. The pistons would cost (I know, this may give you a heart-attack) $1,550.000 USD per set of 4. Yes, this is very expensive. However, these are made for the ultimate performance, and made by the top piston manufacturers in the World - BAR NONE. We don't play around

I look forward to your feedback asap so I can get the design rolling right away.

Cheers,

Mike Norman
G-Force Engine Development
www.mngforce.com
There is no such thing as "Too Fast"

 

That's impressive power gains from the cryo treatment, engine component polishing and port tidying

If you were to allocate the gains which element would you distinguish as the most beneficial for the $$ invested?

 

That's a really tough one. Everything I do nips away at losses to hp. So, each one of the elements you mentioned have practically equal benefits. In a build like this, my goal was to unleash the power being robbed by parasitic losses from friction, and the VE losses from port turbulence at 19k rpm, The port velocity is very extreme at that engine speed and the losses from trying to move a fluid can really be great. There is still a lot to be done like: Cam Timing, Bigger valves, higher compression and other goodies. I would love to see 55hp to 57hp out of this little engine. Maybe even 60hp on good, stinky (Oxygenated) race fuel. The pistons should help get there with yet even more losses of parasitic drag, and raising the compression.

Mike Norman
G-Force Engine Development
www.mngforce.com
There is no such thing as "Too Fast"