400 smoking like a two stroke

[fasthondaman]

One day i went riding and my 400 was smoking like a two stroke and it burns oil bad. Please help. Thanks for any input. fasthondaman

[hondaredrider]

mine was doing the exact same thing only after the second time rinding after i bought it. I had to have the top end rebuilt, cylinder bored, new piston and rings, new timing chain, new valves and valve seals. mine cost me about $600. fairly good price around here.

[bubba's400ex]

it is most likly eather your rings or valve seals. check your compression to see if it is rings. if it is seals thats good for you because they are only about $5.

[Dune Surfer]

Time to build a 426!! Ross piston, hot cams stage two, gasket kit, your good to go. Get it bored at a local shop and build it yourself. Very easy.

[fasthondaman]

I am thinking about 440 or 426. What would it cost and what do I need? I might get hotcam stage 2. Then I might be able to keep up with some of my friends I ride with:) .

[Dune Surfer]

I like the 426 because you don't need to resleeve it and it revs faster. $26 is also cheaper to build. When I built mine the first time it pulled the bolts out of the cylinder. I had oversized bolts installed and it solved that problem. Either way will make a huge gain in power. Still not as fast as the 450's but much faster that stock 400"s:)

[fasthondaman]

426 is .020 over stock right? I think i will get that and how much are oversized head studs and where can I get them. Im trying to get my list together. fasthondaman

[hondajoe05]

pretty sure a 426 is not .020 over more like .060 i think? its 88mm is all i know

[GPracer2500]

.020" oversized = about 0.5mm.

A 426cc is 3mm oversized (88mm vs. the stock 85mm).

[MisterEX]

Jeez does this 400 have high hours on it? I've seen these engines run on the edge of forever without any ring issues. Test compression with the cylinder dry and and then wet. Also look at your exhaust valves...if they look oil contaminated it could just be valve seals.....you can change them without taking the head off with the right tools and while pressurizing the cylinder to keep the valves seated. Let us know what you find....if its rings then definitely go with the bigger bore....port the head, cam and BOOM hold on brotha. I'd love to do mine...but it runs so damn good I dont have heart to tear her down. Good luck and let us know what up

[fasthondaman]

We go riding almost every weekend so it has some hours on it. I think Im going two tear it down a see whats wrong and if its rings im going to put a 426 in it. Possibly hotcam stage 2. Ill tell you guys how it goes.

[fasthondaman]

Where can I get oversized head studs? I found a 426 kit on ebay for 100. I think im going to get it. thanks.

[ilpadrino113]

what company is the 426 kit?

remember you'll need gaskets and head studs and all that

[GPracer2500]

GT Thunder sells oversized studs. I'm sure there are others too...

[fasthondaman]

The piston is Wiseco. There is a gasket kit. I am going to get it and oversized head studs. Thanks

[Dune Surfer]

Originally posted by fasthondaman
Where can I get oversized head studs? I found a 426 kit on ebay for 100. I think im going to get it. thanks.

I bought my oversized studs at Rocky ridge racing and had them installed at a local machine shop.

[johnsls]

fasthondaman,,, You'd be better off getting the JE piston kit.. goto C&D racing (on here) and buy it from him. He can also take care of your cylinder bore too. and with the 426 your gonna want the stage II cam. Just my 2¢