Doesnt it make since that since the put the Scrambler engine in the 500 they would put a 400 Scrambler engine in the SP 400 too? I mean they might want to make some sale, but eventually it would make sense to do so wouldnt it?

 

not going to happine, the sc400 engine is a two stroke and there all done selling thoes next year.the sp400 is a four stroke 425cc engine.
now u might be able to put a HO cam in a sp400, but im not sure if it would work.

later
jon

 

500 HO cam will fit in the Magnum 425 motor. Do a search its been done by some one on this forum.

 

I think the 400 Xplorer already has that roll filled.

 

Yes, if I remember right, someone put the HO cam in their Xpedition 425....which is the same engine as the SP400.

 

That would be me, Fourlix. I put a Scrambler
500, same as 500 H.O. Sportsman, camshaft in my son's 425 EXP. Same motor, except for transmission and crankcases as the new Sportsman
400 (Why didn't they just call it the Sportsman 425?) It took me 3 hours to change cams, very straightforward. Wire the cam sprocket & chain up to the frame so it doesn't jump a tooth or you'll have to retime the whole thing. Release the chain tensioner first. Pay attention to the compression release gizmo on the other end of the cam, the spring can go on backwards. Just loosen the rocker assembly and slide the cam out and the new one back in, covered in oil. I just put the AAEN long duration cam in my H.O. Sportsman,
did it in 2 hours this time, next is a 42mm Mikuni
TM pumper carb, then a 1&3/4" headpipe and automotive muffler (just found a 16"x4" with 1&7/8" inlet and outlet, I'll let you know...
Meanwhile, the 425 EXP gets a 38mm TM I found cheap, and maybe that muffler, ($20!!)
Silly Later,,,,Fourlix
The results of these cam changes has been mixed.
They pull stronger through mid-range, no big loss on the low end, no big gains on top. This is why I'm still working on it. In order for the cams to realize their potential gains, other avenues need to be developed too. Clutch weights and springs, K&N and airbox mods, Pipes and mufflers and even carburetors. 4-Strokes just don't light up with a little modifying the way 2-strokes do.
To get it right you got to get it ALL right, from snorkel to muffler and everything in between. It is hard to beat the factory at their own game.