'11 KX250F Valve springs

Time for a top end on my bike, just wondering if there are any alternative Valve springs i can use. I have PC cams and $400 for just the springs and retainers is alil costly at the moment.

Edited by Bryan Bosch

Xceldyne springs are a good alternative from what I've heard. They are about $125 for the set. Like you, I have a pro-circuit head that needs to be freshened up. I hope the valves are in good shape and I'm not forced to replace them. Are retainers, seats, or guides prone to wear? I guess I will find out what needs to be replaced after I take it apart, but I'm on a tight budget. I'm already going to have to replace the crankshaft and piston, as well as fix some chassis issues. I'm thinking I could almost break even by just buying a new bike ??

Does anyone know the difference between OEM, Xceldyne, pro circuit, PRO-X, or wiseco valves. They are all advertised as titanium, however the prices greatly differ. I don't want to sacrifice power by going to stainless valves but I'm also trying to save some money. Thanks.

Not sure on the wiseco or pro x valves. Speculating on the exceldyne and PC valves that they probably do not have a dish. Meaning there is no small bowl on the face of the valve- meant to help bump compression a bit (same reason carillo pistons have bumps instead of being flat where the valves enter and retract- to bump compression). The delwest valves are really nice valves, and they aren't dished either. The big difference between the delwest and (assuming PC and xceldyne) is that the shaft of the valve doesn't taper and seem like two pieces pressed together like the OEM valve. I was in the same boat about 3 weeks ago deciding to do with my 11. Spend 1k on the motor on parts at cost, or just buy a 13 in the spring and sell my 11 as is. I ended up going with a moose rod (actually a carillo just less money, stamped carillo right on it), new copper/bronze seats from kibble white, new rings (piston has like 15 hours on it). For valves I went with OEM for the simple fact that chaparrel has a promo going right now for 25% off OEM parts and for the intake valves it was like 60 dollars a piece and like 55 a piece for the exhausts. Even at cost the delwest were going to run me 65-70 a piece and in the grand scheme of things i just saved the 20 bucks and put it towards labor to get the crank pressed apart and the carillo rod pressed on.

Stock vavles will be fine to run, just with the PC cams you need heavier springs to be able to handle the cam design. PC wants 354.99, i saw the Xceldyne and it got me thinking, Del west makes PC valves JE makes PC pistons and next in line would be who makes PC springs/retainers?

Thanks for the replies, im just hoping to get some first hand experience with the spring rates ect...

del west makes Pro Circuit retainers, washers and keepers. They are ti, except the washers because they do not move so they do not benefit from lighter weight. The springs I think are made by a aerospace company but not sure who. If it were me I'd use exceldyne components for the springs and the collets, and just go with stock for the retainers. You really don't need to replace the washers, but those are cheap so it is not much more to do that (stock). The exceldyne keepers are actually made for the different valve stem size on exhaust and intake so they fit better and are less likely to cause a problem when you are really revving it out. Valves - del west has their stock replacement which are the best valves for the money in my opinion.

stock are a little cheaper and are good quality. You will need to get the valve stems replaced with the seats...it will make your engine run so smooth it will be unbelievable in the beginning, especially with copper alloy. The seats and guides (sopper) can be had for around $500 installed from various places. pro1racingheads.com is a good place to start.

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