i was wondering how high u can rev the scram,and if there are any mods you can do to the engine to allow it to rev higher therfore going faster and putting out more torque,is a modification like this expensive?what sparked this question was when i was riding a magnum it didnt feel like the engine was revvving really high it just felt like it had alotta pulling power but not revving high enough to reach a high speed(above 50mph)

 

A scrammy will go well above 50mph. I think about 7500 is near the top rpm. The top speed of the scrammy is somewhere around 60-65mph.

 

The book says 6500 rpms max. My tach agrees. I asked my mechanic this question just a few days ago. According to him much more than that and the engine will implode. It is not designed to rev hi like other motors. It is, after all, more of a utility type motor. Great torque at low rpms. It's what make the 500 Sportsman so great and holds the Scrammy back.

 

I aggree with Fishslab. This motor wasnt made for high RPMS. It makes its power at lower RPMs so there would be no need to raise the rev limiter

 

Just thinking about it, I don't think it is actually rev limited by the cdi except in reverse. I believe it is limited more by it's own design. So with a new cam and some stiffer valves springs you may be able to get up a little higher. I know running down a long downgrade I hit 6800 a couple of times and the motor never cut out like a rev limiter.

 

another reason i asked about this is because i raced a 400 ex and as we hit the top end we were neck and neck and it seemed as if mine stayed at a certain rpm and his kept revvin,we ran full throttle for about 1/2 mile or so on pavement neck and neck until the top end,he pulled ahead 2-3 lengths and it took awhile for me to catch back up

 

Since you are on the 2x4, go up a tooth on the front sprocket or get a taller rear tire. Or both? That should get you out in front. Are you running a clutch kit? If not you could be running out of clutch ratio way before you hit top end. Just some stuff to think about.

 

i dont have a clutch kit,all i kno of is a pipe and along with the pipe the woman i bought it from said she adjusted something to make the air/fuel mixture insync with pipe because she said it was running too rich or lean,i forgot which 1 and another reason i may not have been running as hard was becase the day b4 we raced i burned the belt trying to climb over a fallen tree,i thought the tires were spinning and all or a sudden i saw a cloud of rubbery smelling smoke rise from under me,the belt slipped for a little while after that but now it seems ALMOST normal,it doesnt feel like it accelerates as hard but it still has plenty of power in the mid range

 

I know exactly what you are talking about. Low and mid range feel fine, but on mine the top end seems way slower. I burnt my belt a little just like you and I plan on putting a new belt on there soon. Does your top end feel a lot slower too? You can also tell that low and mid range are just BARELY off, and at first i didn't even notice

 

it ran strong off the line other than a slight slippage of the belt and when we hit top end it acted like it was getting tired and couldnt pull anymore,after i change the belt i will look into regearing,new filter,clutch springs,etc,i felt like i should have won my more(when i did win)
the 400 ex and i raced about 500 on grass:tie,long curvy dirt road:i won by a little and then on pavement:lost by 2-3 lengths

next weekend we will swtich and see if it has anything to do with the rider,(me 15 yrs old 6'4 225)(him 5'10ish about 180ish 20yrs old)i think it has somethin to do with the aerodynamics too and the 400 ex is more aerodynamic due to those lights on the scrammy