I just bought my '01 400ex and was wondering if anyone would help me out by telling me how much a 426kit will cost including labor and all the parts you will need? Thanks a lot. I have heard that the 426 is as fast as the 440, is this true? Thanks a lot.

 

It would be cheaper for you to mod your 400ex motor to a 440cc. I heard that the 426 motor has problem in 4 wheelers. The trans is not strong enough to handle 2 rear wheels. Also think about paying over $2000 for a 426 motor if not more. Then add in carb electrics and a custom exhaust.

 

Exitic1 that is not the 426 he was talking about. He meant the 426 kit instead of a 440. Do a search for 426 from a person named AIR or CLUTCH, they both have put this on there 400's and they should be able to tell you how much and who could do it.

 

The costs will vary depending on what bolt-on mods (pipe, jets, filter, etc.) you go with. I will assume that you do those mods first, and then step up to the internal mods.

As far as the internal engine work goes, here are the costs if you order the parts yourself. You can get the piston from Wiseco for $112 plus shipping. You can also get the gaskets from Wiseco for another $25. A cam from Webcam will set you back $150 plus shipping. You will have to pay an additional $170 for a core charge which will be refunded to you when they receive your original cam. If you do the work yourself, you will only have to pay for boring the cylinder (usually about $40-50) and having the gear mounting flange on the cam swapped (about $15-20). So, if you do the work yourself, you can accomplish the INTERNAL ENGINE WORK for about $350-$400 (depending on machine shop costs and shipping costs).

The only difference in costs between the 426 kit and the 440 kit is the cost of a cylinder sleeve ($62.50 from Wiseco) and the cost of changing the sleeve in the cylinder instead of a bore job. I found a shop who did the work for $75, or Wiseco will do it for $50 if you send them your cylinder. As you can see, the price difference is not that much.