I'm thinking about building a (even more 'rocket') engine for my cr125 (1980) competition bike. With programmable CDI and mügen porting on a stock cilinder. I'm pretty new to 'tuning' so all info is welcome! 😁

There is one video where one Guy made 59.5 whp with ported esr 325 cr250 but that dyno might show too high figures, this dyno showed esr 325 kit with fmf and v forces making 50 whp

i dont know about that…The older husky 125s used a T port exhaust and very yamaha like cylinder. For us, the current ktm/husky jetted right makes incredible stock hp and properly built even more incredible mod hp. That said I havent tried to jazz up the old school husky so maybe your on to something

@@HPRaceDevelopment I was thinking the 98 up like Chiodi raced to a world title with. I have a 2000 and a 2002 that needs bored and plated so I thought it made sense to work it over and see what I could make happen. Fast by Ferraci has a few JD race ignition cdi’s left over with some pretty good maps. With more R&D I imagine some more power could be found. Thinking GNCC XC3 ripper and a good setup for whoops/SX style stuff.

this is for all 2 strokes we offer cdis for the ktm250 and 300s in your case what you want to change is the question

@@HPRaceDevelopment After watching both of your videos its clear bikes ignition curves respond and act differently based on what parts you have on the bike, mine is almost fully suited up with engine mods beside the high performance 2 stroke head which I will be picking up soon. As in what I would like to change I have no idea 😅but a more optimal ignition curve would be nice like shown on the dino.

everything is kinda like a delay on these due to pipe temp taking time to change so u start pretty early just barely taking some out - and work from there

the straight ignition tests are good for us too, revisit what the engine likes. i was really shocked by some of it at spots how close straight was to a nice curve. years of 2t advancement for measly gains ha

The powerjet properly utilized increases bottom to mid while maintaining good peak.

No, only 300 so far

not legal for any racing we do...anyone who says they do anything to them that will pass the rules is either lying or cheating

@@HPRaceDevelopment We are in Northern California and only have ama races for Loretta’s. For that we use a new stock bike, but everything else allows full mod 50cc motors we also have Mammoth mountain that allows big bores most run 60cc but the Cobra 65 piston is dimensionally compatible also but may not be any better going to 65cc. But it sounds like you haven’t done mods to the 50’s So Cal and Nor Cal have some fast minis think you could build one that would be better? 🤔

@@raymondharold5973 The current 50 from cobra jetted well is quite good. id be very surprised to see one thats still a 50 be better overall engine combo. Any peak gains you make trade power width - which is critical on a single speed The 60s of course can be very stout vs a 50

@@HPRaceDevelopment The mammoth motors are definitely faster but the mod 50’s some are and some are slower but with a complete system wide change done well some is left on the table you would think, don’t you have a CDI that could be programmed or is there not enough business to justify doing that. I’m wondering what a project like that would cost, I’ve seen that you take a system wide approach and that’s the only way to not miss some potential performance. Any interest ?

@@raymondharold5973 always interest - just never much free time! We are adding on and making a lot of shop changes for the next year - hopefully by fall/winter we have that rolling and I can have some more free time for projects

Not my area of expertise. Im sure someone does.

Than what? An engine need the proper amount of timing for the design at every RPM.

I have 2 dynos one is a water brake and the chassis dyno is inertia with a brake we can use The inertia is far better over the years - and ironically now lots of nascar shops have switched over to inertia as well

@@HPRaceDevelopment okay thanks, So you usually use only inertia on your chassis dyna without using the brake? is with brake not better for adjustments because there is more load on the engine

If you want a real race bike.

@@HPRaceDevelopment so I can send u an ecu and u can tune it for a yz250 that just has an fmf system and vforce reeds?

@@adriangalvez5104 no. Requires a new cdi

Paying clients get that!

i did

You have to ask a little better here. But those are absolute values vs TDC.

I thought they were , because the timing retards as revs increase which is inverted for a 4 stroke .lf you started at 2 degrees firing couldn't get to after TDC, it's just not that obvious for a novice . The burn is inefficience for 2t , i wonder how efficient a jet engine is ? They do have power to weight %. Thank you .@@HPRaceDevelopment

then dont watch, thx!

You mean the bikes that make shit power, overal run very poorly, cost a fortune to tune if you wanted to tune it? No thx!