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190th
Edited Date/Time
3/14/2020 3:48pm
Since these 2 bikes have relatively large valve sizes and ports, I’m considering building a 270 or 280cc motor with that head configuration; either may be a nice midrange engine? Anyone have any experience with the KTM? I’d think the Honda is too new for that kit yet...
Have you considered a tree fiddy?
The Shop
percentage wise - it's equally better everywhere.
KTM's massive intake port, and large valve sizes with cam lobes that are like japense 450's (actually larger) make for an engine that can support more CC's.
The new honda will likely be very similar. The short stroke, large bore, large valve combo from honda is likely going to love a big bore....
The issue with stroking becomes much more challenging too. Pistons already have the wrist pin as high as it can go, nearly into the oil ring.
Rods are generally quite short for packaging purposes and weight...and in the case of the honda, with a stock rev limit of 14500 - adding piston speed due to longer stroke is risky business for the average consumer.
Not the mention the crank will become less supportive of the rod pin, and potentially cases to clear a useful stroke addition to get meaniful CC's. The added piston speed would be great for the large valve/likely large port honda will have for air flow - but the larger piston does the same thing.....
Depending on how the cylinder looks - we may entertain a big bore for the honda. The ktm kit has sold really well to vet customers and offroad guys (even though I totally agree a 350 makes a lot of sense)
I'm interested in your big bore kit for my 2017 Husky FC250, I see you offer the kit for $700 but then it looks like the head mods can cost twice the amount of the kit.
So while I was getting the 270 set up, I was riding a 2017 350, which I loved. The motor and handling were very good for me once I geared it down, but since I had the 270 waiting, decided to sell it.
I finally got the fork issue worked out on the 270, it had 4cs but I did a SSS conversion. Only a couple rides now, but I have to say that I may like it more than the 350. Definitely more power and torque across the entire power curve than any 250 I have ridden and in some ways I think it is easier to ride than the 350, because you ride it that extra bit more aggressively. Can also pull tight rutted corners with minimal need to clutch it
Derek knows how to get the most of these bikes and I can recommend his services, although Derek, you still owe me a side case and one of my motor mount bolts has a stripped head!
I have also have a chart published with 270 kit with head and cams and a dual injection set up with GET system mapped properly that is well above 50
Proper porting on the ktm requires lots of work and isn't just grinding away material.. if we offer it by hand on a new un used head it's 550, no assembly.
Dollar per dollar the kit is a killer value for the gains, porting and cams are big budget R&D items that I have invested way too much into for the avg joe market (pro race market really only avenue now that can afford and needs high level development on these new engines) luckily a few have invested to get the best they can it allows our r&d process to advance forward every year.
On the side case
The throttle body blade kit is like 240 retail and mapping is 100 on oem ecu
It gets pricey past that quickly.
Next level item I think people don't put enough value on is the ecu.... for the little more price of a full ti exhaust system for a honda, we have the GET dual injection set up tuned in really well and is a great addition. Proper ecu tuning from knowledgeable shops such as aforementioned Ellis or dean or PC etc can really do a lot in feel and character of the bike, plus unlock that last bit of power. I'm a GET guy... you kinda choose one or the other from a cost of the tuning software aspect... With Launch control, traction assist, and wifi tuning for simple map changes, it very useful for me.
I've worked with the vortex stuff and find it to be extremely good too
So I got a really good deal trading in the TC250 on a 2017 FC250, it's a fun bike that I can ride at a good pace for most of the day now without having the same arm problems. I got such a good deal on it that it almost didn't make sense to get another 350. So after seeing your kit it's really peaked my interest. If I could get the power your chart has which looks to give me allot more bottom for just under $1100 I'd definitely be down for that.
I actually love ripping around on the FC250 even though I've always owned 250 2-strokes or 450's.
mxjeff575, have you rebuilt your 270 and if so what head gasket did you use?
Pit Row
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