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Whati can understand epoxy seems to be the best option to keep engine response etc, but im wating for TDC to get in to my parts properly and thenn i will post info in here.
I will try that epoxy, thanks!
Will remove the sticker for more factory look.
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As for powdercoat on engine cases i don't se any bigger problem, it's Good to let all heat you can out, but i think it is a smaker issue with paint on the cases then what it would be if you painted the cylinder or head with a thick paint.
I don't know what Honda used to paint their engines with back in the days when they were red or black, but keep in mind that the mugen 125 had a red cylinder and head to, so it can't be that bad.
Will go for a carbon skidplate to..
Been bussy with my enduro racing latley so it's still where í left it in the last post.
But the parts are getting done over att TDC, got a mail with some pics, really fun to see the progress of tuning and getting updated
about whats happening.
But we ran in some issues, the Phat head turned out to be a problem to order, sense phat head has been bought by another company and the parts were in the transfer between tha companys.
So we decided to go for a VHM head instead that is a european head that is really big over here, but it turned out that the 99 VHM heads were discontinued..
So Brett att TDC milled out my old head, and made a new insert with orings instead of a gasket.
Here is the final result, he is finnishing up the cylinder now so soon i can have the bike up on the dyno and hopefully present som good numbers.
A engine that grows in cc's, needs more port area than stock, if not , it will not run well.
Aslo, needs to have a balance of torque and rpm. Torque makes HP as does Rpm, as long as rpm does not drop faster than torque , power goes up. If not , rpm goes up and torque drop faster, than it will rev and not make power.
it cured your woes. Brent, I like your reference of the shop vac and exhaust. If we were to measure an
engines air flow without proper pipe effects it would be surprisingly deficient without them. I also
feel you have the upper hand on this, to fill in the blanks you evidently know the std volume of
the crankcase and the added displacement which would numerically add about .1 on its volume #
( from 1.416:1 to 1.510:1 or similar) and also know when its too much for what you intend for Tumic's
motor or in alignment with the pipe that will be used.
It is very seldom I hear anyone use reference to crankcase volume so I find that very intriguing, my
knowledge of it is very dated so I was hoping you might have some fresh input that does not under
mine your business at hand (or in general). This is what I understand, 1.2:1 is on the low side, any-
thing over 1.5:1 is on the high side (too little volume). Your input would be quite valued.
Now on your selection of pipe to crankcase volume, are you evaluating/selecting, modifying or doing
custom pipes to meet the engines needs? I realize your direction is often limited by the customers
budget and the best you can give them in return within that.
Since theory in practice often has different results than expected I am interested in what works for YOU! :-)
Regards,
R
Riv . I think case comp all depends on the timings and transfer duct volume /shape/angles and of corse the pipe.
I have tested different transfer tunnel volumes /angles /pipes on the Dyno on a couple different engines .
One case reed I did made best power and Torque with a low 1.25 ratio. Case comp must be measured and
taken into account on all builds.
a go to in one of the main legs of your builds, not that I doubt it at all. Imo I think it adds
another layer to the build that either tuners aren't saying their doing or just sidestepping
it totally...?? Honestly I've used some software from about 93-2005ish with great success
& only input I had used on crank comp. was within its reed valve program, now I'm wishing
that I had played with case volume more-especially on some stroker motors!
Do you work with any vintage builds? If so I know of someone that really needs some
direction on a stagnant project, I'm pretty sure they have a mismatched pipe, a target
RPM that is not achievable due to mechanical limitations & yes certainly a case comp
that is too low for its down sized displacement. I don't believe money is as important
as completing the project, if remotely interested I could fill you in, with about a 5 minute
phone call.
Pit Row
I split the cases and got them water and glass blasted.
Looks like brand new, did not find any company that could anodise the color i wanted on the cases so went for this option instead.
Blasted some other parts to.
When we split the cases and removed the Rad Valve i saw that the reeds were all gone, about 10 hours ago the looked like new so i dont know if it is the Avgas 100ll fuel that took uot the reeds?
The carbon part is undamaged but not the clear plastic parts.
a work in progress pic of the cylinder, the cylinder is back from replating now and will be shiped back to me today, i will post more pics of that when i get it.
Got a new Sunline brake lever and a Cycra stadium plate ordered from BTO sports to, so soon i got all the parts i need to put the bike to geather again, until then i got som work to do on my new 450 that i gonna test a Öhlins fork on.
https://youtu.be/txd6umaG7Qs
The parts looks really nice and i can see a good amount of work on the cyliner.
The miss match problem is now gone
And here is the new head VS the old one
Started to put it back to geather las night and started to play a bit with the new valve cover.
We still got snow at home...
connection for the sensor on it, do I just disconnect the cable from the old one, its a 2007 cr125, unsure if it matters,
may just try it.
q2, anyone tried running them without the power valve in place, thinking of either locking it open or removing it to see how it
runs, eager to try,
nice work, now post a vid,
On the shifter kart engines they remove the power valves and blug them, but i hav never seen any dyno graphs on how much it effects the powerband, good or bad.
You should be able to just disconnect the cable, but i saw someone on thumper talk that had a PWK TPS kit for cr250, maybe he can fix some 125 kits to for the newer TPS cr 125 bikes.
I will post a vid when it gets on the dyno and the first test ride
swappin with the pwk, it measured between 38/39mm, I think I need better glasses,
tried any advanced / retarding at all, read it was better to keep it retarded a little like me,
wish I kept the stock muffler
back on, cheerio bro next time answer a bit quicker i'm on a timing limit,
Right now im just half asleep and will just let the pic's speak for them self,
The 05-07 pipe was a straight fit, so if you ever need a pipe for your 02-04, the newer pipes will fit.
Post a reply to: My 02 CR155