Finally got an actual 250cc clutch (cn 250 clutch) put on my hh250ss (been using a 150cc clutch and bell and torque spring since i got it last year) and now it has alot better low end (obviously) and now runs 43 mph but it seems to up shift wayyy to early in high and low gear. I dont know what size rollers are in it but ive tried a red torque spring with same results. There is no smooth transition from start to max speed it just spins tires then boom its bogged down because its already shifting up to high to soon. Hope that all made sense.

So question is what would cause that type of shifting and what is an overall good combo as far as sliders and springs go? Whats a good clutch other than the DR pulley clutch?

Next i wanna upgrade the motor and was wonder what would be recomended in that department. Is there a BBK? Head options? Camshaft options?

I run 18g sliders with the red main spring on Dr. Pulley clutch and variator.

There is a BBK with a bigger cylinder and piston. There is also a port and polished head you can get a 2 cams, a rock crawler and another one that is more for top end speed.

Hammerhead also has a good upgrade kit with a UNI filter, high performance exhaust and upgraded carb jets.

You're running a clutch for a CN250 in a Hammerhead 250 SS? That should be a CFMoto engine/trans and I believe it takes a different clutch. The variators are different for sure between the CN250s and the CFMotos.

Dshock thx for that info and Sockman the CN250 clutch will work on the CF but the CF will not work on the CN because of the size of it. 65 bucks vs 180...

Ok. Never tried it. What belt are you running? Do you have the CFMoto variator?

I'm running 18g sliders in my setup. I also have 24" rear tires, and running the 12t drive sprocket. Have a black torque spring, and Dr Pulley clutch. Mine won't spin the tires, and I'm still trying to get the clutch dialed in. Wish I could help more.

As far as i know its cf variator and its the Mitusboshi belt. I wanna upgrade to 24 or 25 inch tires sooner than later. Its perfectly drivable as is i just feel like its upshifting way to soon. and in low gear it feels as if it upshifts and bogs for a few seconds and then picks up again and screams.

Mine, too. I tried changing the engagement on the clutch, so that it hooked up at a higher RPM, but that made it worse. I think basically what I did was make the variator engage faster, causing it to start off in a higher gear ratio. I'm going to put the clutch springs back so that the clutch engages at a lower RPM, but then going with a 15g set of sliders in the variator. Also, I have a black torque spring that I have no idea where it came from. Might go with the yellow one, I think.

Whats weird is the fact it drove almost perfect with the 150 clutch bell and spring but the 150 spring had to be forced on the rear pulley and so it would jam and keep it in a higher gear all the time. But it accelerated good other than never going all the way back to low

the cn 250 clutch and variator will fit the cfmoto. ( digger did that with his ) but you need to change the variator, clutch and use a cn250 belt, if not the cf belt will ne to big. it makes the engine spool up quicker

Hmmm i wonder if i have a cn variator then because i noticed the belt at rest is tight but does not go all the way down to the boss in the variator

Here's a pic of mine. Should give you an idea of how large the clutch/variator are on the CFMoto.

My belt actually sits up outa the rear pulley a mm or so....what kinda tires are those?

That makes sense, since the CN250 pulley is smaller, right?

Idk....i was thinking the pulleys was the same just the clutch was smaller than the pulley for the cn and same size for the cf....may be completely wrong tho which would make sense and probably means my shifting is belt length related. Ill pull it off tonight and compare.

Ok cf clutch pulley is a little bit bigger. So im going to put the cn clutch on the cf pulley and see what happens. Ill order a cn belt soon.

need to change the pulley to a cn also,

Ok heres the combo atm...cf variator belt and pulley with cn clutch. Seems to accelerate like it should but its lost about 5 mph top end.

Interesting. So you can mate the CN250 clutch and bell with the CFMoto clutch pulley?

Can you post a pic of your setup?

Yes you can put CN CF and 150cc clutches on the CF clutch pulley.The CN clutch hole is actually a little bigger than the CF and the 150cc clutch hole i had to enlarge just a wee bit. Ill try and get some pics for you tomorrow. Where are people getting the bbk from? I cant find any in stock.

I'd have the head port & polished before I'd consider the BBK.