Відео

@@fredmitchel1236 Ill never understand how people assume an hour number. The math is simple. Whats the applied force, whats the applied cycles, whats the material choice, whats its high cycle fatigue life - convert hours to cycles and you have a change interval This piston looks fine, is dimensionally same as new and shows no “signs” of wear. You change pistons in race use because its the stress crack fatigue you cant see that causes exploded parts, not the visual wear you can see

Not bad but the newer ones make a lot more

@@user-sp8eb6iz7f All kyb “twin chamber” forks in use with the exception of the yamaha in 2005 and up to 2007 kawasakis are the”speed sensative fork” or triple s. What you have been told is complete bullshit that yamaha has a special of different kyb. The kawasaki 450 in 2009 on until it went to showa was the same design yamaha uses, the honda 450 that used kyb was same until the airfork switch, the suzuki 250 is same kyb, and the modern kx250f is same kyb along with triumph. There have been small changes for reliability since 2006 but nothing major on the design. The current showa 49 spring and kyb 48 are nearly identical - we have 2 videos showing this

kids and people like loud - makes them think its faster

@@cagr4249 what

I also preached this to many stock class racers parents on the ignition timing and modifications that actually alter stock machines

@@jellolon8435 lol - i think some ultra nerds (EE majors) have variable ignition curves for points bikes too! Way above my pay grade

@@HPRaceDevelopment Nah its a 1979 50cc so I think ill be fine staying in my mechanical lane :D was a helpful watch anyways tho. 34.5° Before TDC by the previous owner was a bit much IMHO.

on wheel

@@Jb-mp1in why do you care what the number is…

@@HPRaceDevelopment no I'm asking why would ktm say 57 hp stock ?

@@briantanaka2185 our video shows the results

@@HPRaceDevelopment yes i try your MXA MAP this coming event !

@@briantanaka2185 we didnt think it was best - i think dyno charts show stock to be best

@@HPRaceDevelopment hard hitting you mean?

@@briantanaka2185 none of the “maps” amount to hardly any change in performance. the oem “tuning” doesnt do hardly anything the actual maps

sounds like you are mis disgnosing the issues

Not a glitch. Just a challenge of getting efi to run right on a 2t that people didnt realize how good carbs are

I assume you own a kx450. Find someone with that bike, and those parts in the tx area who is open to doing it and I will.

@@denniswilder3014 Depends on the racing series. In usa no wheel speed sensors are allowed - which arent too useful when trying to compare rear to front wheel speed when most good starts the front tire doesnt spin for a long time. Accelerometers are used in some systems

@@denniswilder3014 02 on a 2 stroke is about worthless. You can prove me wrong and I would be excited about it… The oem ecu can not be changed for additions

@@HPRaceDevelopment talk to iantomassi race engines. And look at what they build for snocross and cross country race sleds. Yes they are variable clutching but never ever at the same rpms.

@@denniswilder3014 Its not even remotely alike to mx or offroad. Sleds are very much at consistent on the pipe rpms. secondly - what 02 you read is not the 02 that was in the combustion chamber and thats all we care about for tuning. the delay time pending where the sensor is placed is huge, and the closed loop correction time is far too long on an offroad bike to be function. Its too slow for 4 stroke mxers and offroad bikes with fast response accurate ish 02 feedback and correction. The fuel you supply on a 2t via a tb takes over 10 cycles to really be noticed in the chamber - and would likely be 50-70 cycles before an 02 sensor would notice it - if it were accurate which it isnt. Honda has a full sae paper on the subject if you wish to dig into it. The moto gp teams were never able to make efi work better than carbs and for all those reasons plus many more i havent touched on For dyno work you can make an 02 system somewhat functional and create cheat offset tables as to when its accurate and when its not but its not very useful to accomplishing the goal of good running

@@HPRaceDevelopment pipes in snocross are no where near the same pipe temp. The rpms are all over the place just like moto cross. And if things are ever variable in moto cross why do you just post about peak horsepower numbers that only happen in a short rpm range. The new 02 sensors respond just as fast as a servo motor on electric power valves and all the sensors on the efi bikes.

@@denniswilder3014 We report the entire wot curve - not sure what what videos you have watched. You can argue all you want. Go get a sled shop to prove me wrong - as I stated Id be happy to see it.

@@denniswilder3014 Welcome to the party. In ama pro racing, such as sx and mx, you must run stock castings and cases, cylinder. I even believe our billet head is illegal but has been overlooked by rule makers. The rules in the usa are to protect the oems from outside competition and new companies

@@HPRaceDevelopment the only thing really holding the yz back is the exhaust port is a little small. Why not port into the water jacket a bit then weld it closed and machine it. In pro stock 800 sled class its stock cyl. And my engine guy does that. More than one way to skin a cat

@@denniswilder3014 There is a lot more holding it back than that. But assuming some simple welding could allow us to widen the port, you would have to redesign and remake the powervalve to full width of the port, which requires remachine cylinder slot for that - could potentially hit water - not easily access-able areas to weld. The side ex port dividers are in the wrong spot - youd have to remake those somehow - and welding its gonna happen in that spot the side powervalves themselves would then be in the wrong spot once those ports were moved and widened requiring a redesign of the powervalve arms and system Its too expensive and time consuming unlikely to work consistently, and not sellable. The difference between a pro race team that has funding - and a public shop like mine is immense. Everything we do has to make sense.

@@take5th Hmm triumph dealers claiming big numbers and hyping it up. media outlets all said it has “more bottom” than ktm and was hybrid of ktm and yamaha

@@HPRaceDevelopment ok. I saw a couple guys ride, on youtube mind you, and say it was more progressive and broad than the competition, preferred low revs. i certainly dont know.

@@take5th Does our dyno chart show power focussed at lower ranges than the ktm? Where does our chart show the highest value of power on the triumph? As far as I can see - its not stronger than the ktm on any point of low end and peaks right near the limiter. So maybe the reviewers need a little more accurate butt dyno…

No mx bike auto adjusts. Luckily the stock tune up worked well with these fuels. Selecting race fuels for many people is about selecting a fuel that works well with the stock ecu tune.

@@HPRaceDevelopment good to know, thank you! Have you experimented with 100 LL ave gas? Asking because that’s available to me at a very affordable price. ( 22’ 350 xcf )

@@franzv3172I’d be interested in your opinion on 100LL for both 2T and 4T. It’s super affordable and readily available.

@@HPRaceDevelopment​​⁠I’d be interested in your opinion on 100LL for both 2T and 4T. It’s super affordable and readily available, lasts for a long time.

@@motocross402 terrible 4 stroke fuel.

It is...of the 16-22 generation which performs a heck of a lot like the triumph.

Old ktm engine, warmed over. New ktm power comparisons, please.

@@MrKips1 It is compared to a new ktm

​@@HPRaceDevelopment i meant like literally a straight copy of a ktm 250f engine 😂

@@adriangalvez5104 its pretty much a straight clone of a ktm. They have a few changes such as a twin compression ring piston which is bad generally for power - and its head is like newer ktm engine port but on older ktm engine design.

Off our website!

@@HPRaceDevelopment It made 50 hp with this map and fuel

@@wreality4712 dyno is at the wheel

@@elkku2140 we were one of the first to sell this which is now wide spread.

@@HPRaceDevelopment so it must be good. Is reflash a must or can I just run it with stock mapping? Bike is 2022 ktm 250 exc tpi.

@@elkku2140 I know people who run stock

I wouldn't called this "witness" marks as if a piston was kissing a head. What happened was the crank got worn out to the point the pin holes for the crank pin got loose enough to allows the crank to start splaying and every load cycle it fretts on the pin. So I would call it "fretting" myself. While most people will never load their cranks enough to cause this issue, in his case he likes to scream this more than we would like more often than we would like, routinely hitting 14000 rpm - which is just brutal on parts.

@@HPRaceDevelopment Sorry, this is going to be bit of a lecture, but, there may be things you didn't know? I taught measuring and 'machine shop' at MMI for 3 years straight, usually double shift, sometimes triple (and I was good at it as I trained as a precision machinist , finished training 1975, yep, I'm old) Witness marks are any time one rotating part has rubbed on another,either rotating or stati onary you see inside front edge of fenders where tyre 'grows' and wind pressure pushes it down slightly. Section I was trying to explain was center of crank pin where bearings were rubbing not the outsides in fly-wheel. Fretting is the flywheel moving in and out due to imbalance on the pin (as you pointed out) although that looked more like galling as fretting doesn't occur across the entire inserted length of the pin of flywheel bore and is usually a dull/worn area. Yamaha XS650 is well known for it when revved to 9,000 or more (although center section separates around 10,000 even if welded) I've been re-building cranks since 1978, done thousands including teaching few thousand people how to do it. Three cylinder cranks (old Suzuki's) that someone else took apart without marking alignment are a lot of 'fun' when you have to set at 120 degree throw. with parallel pins on mains so have to start degree measuring.. You can get away with 14,000rpm on a two stroke (for short periods) a four-stroke would show severe Brinnelling when things 'try to escape' on overlap and the needle bearings don't rotate as pressure is forcing two hardened surfaces together nway above the design limits (and why high rpm motors use oil wedge/plain bearing). Early YZF and RMZ (or yellow Kawasaki's) had a real short design life when new (less than 35 hours for racers, less for super-cross) I haven'tdone anything with them for 20 years or so, last one I did (YZF250) got national rider from top 120 down to 28 position after racing at Loretta Lynne's. Few people seem to know you can diagnose what rider did on a roller bearing crankby marking crank-pin to flywheel position before taking it apart. Major wear on top or just after TDC is physical 'something' in head or more likely pre-igniton/detonation, (VERY common on Harley's lugged around at low rpm) worn or grey all the way around, lack of maintenance/dirty oil. Brinnelling and wear at bottom of pin is always due to over revving (also common on Harley's) I'm not a Harley guy but youe wouldn't believe how 'upset' they get when a 'Jap-crap'riceburner mechanic tells them what they did. (one offered to buy me a plane ticket back to Britain, another (Cajun HD instructor) needed a translator, but he ended up canned after telling female student she should be barefoot and pregnant at kitchen sink , not trying to fix Harley's. Hope you made it all the way to the end,I know it's a bit much.

@@1crazypj Dont take offense to this but - as short as I can type it - the pin was fretting. a not galling. It created a visible but not feelable impression. Galling is the transferring of material. The main center needle bearing created wear impressions yes. The issue on this crank - that im telling you - we analyszed more closely post video was the crank pin holes wallowed/egg shaped out and became loose allowing the crank the splay. As a top notch instructor you should realize that the crank bob weights themselves create a moment that is always trying to have the webs either push apart or pull together each load cycle - since the bob weights arent in line with the load force I didnt read your whole post but i think we are on the same page on most just not all

@@mahaniamir We did it all and never published the video. I will revisit it on multiple bikes in one video later.

@@mahaniamir Got sidetracked on a bigger project on this bike

@@kanesaw7456 We havent - maybe someone has but getting that stroke to work on a yz65 barrel would be very difficult - bigger isnt better in 2 strokes unless its built properly