What is the best aftermarket brand pistons,... and WHY is it the best ?

[tri5ron]

The WHY ??? part, is far more important to me than the brand name.

Please don't just start listing the various names/brands, if you don't have anything to support it with.

I'm thinking it may be time for me to step up, and freshen my top end a bit.

You all know, how I am a Open Desert, TRAIL rider,...
and I hold the RELIABILITY factor of the 400ex, as a TOP PRIORITY.

I am not interested in being the fastest dumbazz out there, and I couldn't care less about trying to beat a 450R.

I am far Far FAR more interested,
in maintaining a near bullet proof (mildly modified) machine,
that will perform very well, runs on straight "pump gas",
never over heats,...
and comes back to camp from a 40 - 50 mile ride,
under it's own power,...

every time.

I am considering going to a 416, @ 10.5 - 10.8:1 compression.

No,...
I will not go to 11:1.
Remember, this is a TRAIL Bike.
not some wanna-be pro MX'er.


I MAY go to a stage 2 HC, or possibly a comparable cam.

My current engine performance mods, that will in all probability remain are,

Open lid airbox with Outerwears,
Full Big Gun system, with quiet core,
Sparks +6 key
'05 450r Carb (re jetted of course).

I MAY consider a P&P job, but I doubt it.

and I am considering adding a larger oil cooler, GTT HD studs, Spal fan,...
just to play it safe...

and Yes,... I will go to a CRF timing chain.

I already have all the popular "Budget minded" suspension, handeling, and comfort/safety mods,...

as well as a bunch of bolt on accessories,
(that half of the membership here, thinks is sacrilegious to do to a 400EX).

Again, it's a TRAIL machine.

Not a racer,... and not an unrealistic expectation of it's potential performance capacities.

at Best,...

it's a nice XC/Trail machine, with a rear rack and cargo bag, stuffed full of lunch, cold brews, and some target shooting "toys".

So back to the question.

If I WAS,... to step up to, a 416 10.5:1 - 10.8:1,
What brands of pistons hold up to the test of time, better than the others,.... and WHY ???

on the same note,...

What brands should be AVOIDED,...

And W H Y ?????

This could get interesting.

[CJM]

Namura I would avoid like the plague. Everyone I have ever seen had issues with thiers and in a friends case his bandshee blew up after 6 hours of use but had zero issue when we put wisecos in.

Personally speaking I prefer wiseco. They are pretty good, never had an issue with them and they are slightly cheaper than others. JE is also quite nice but I never spent the coin on them and people say they are better-not sure why to. No expierance with CP.

My vote goes to wiseco, Ive ran 2 of them with no issues, my friends run them and have no issues either.

As for you build, I would do a 407. Compression is gonna be power-not a larger bore size. I think you will be happy with a 10:1, 10.5 might be pushing it with the sparks key Ron-might make to much heat.

The 407 10:1, sparks key and the cam. Should be a reliable setup. Friend of mine runs 11:1 407 and HC stage 1 and its got plenty of power. We also run in the sand/desert type terrain (its a large sandpit with woods) and never had an issue with the 11:1s and heat. I hardly ever run my spal fan.

Good luck with the build my friend.

Marc

[Stickman400]

Throwing my hat in the Wiseco corner too. Had 3 other friends and myself put them in their machines (one 2 stroke, the other three 4 stokes) and never had a problem with them. I'm running the 407 with 11:1 and Stage 2 HC and had no problems yet, haven't really put any time on it though.

[crownandmonster]

I have always ran Wiseco or JE in my powersports and I have never had a piston/ring related failure with many hours on the pistons. We always run JE pistons in our dirt track motors (small block chevys), again again have never had a piston or ring related problem. They Also seem to stand up to heat a tad better as we can run them a bit leaner to get the most power out of them with the JE's as compared to something like a speed pro. You can always tell when the cheaper pistons have been run lean as they have pitting on top of the piston where it is literally buring a hole through the top of it.


An 11:1 wiseco with stock 400ex gaskets is going land you somewhere around a 10.5 CR. Throw a STG 2 HC on top of that and you might get away with your 3 degree key. I would have to stick with CJM on this though and recommend a 10:1 piston and 407 bore for your wants/needs.

[Pipeless416]

JE seems to be the more "premier" brand of pistons from the reading i have done. according to my research, before 1999, there was a big difference between the actual finished product tolerances between the two. after 1999, JE and Wiseco merged but still kept producing their own products. however, they did share their "best practices". of course this leads the two companies to basically create the same piston with slightly different measurements. essentially after 1999, they became very very comparable. with four stroke pistons, both companies produce their pistons with extremely small tolerances. chances of having a problem with either are very low, but wisecos are cheaper, so they get my business. as long as the rings are gapped correctly, the jetting isn't too lean, the oil is lubricating well, and the circlips are in good its very unlikely that you will have a piston related failure.

with your list of "wants" for your engine, i think you should just buy mine so i can shove a 650 in my frame :D

[dxcody]

My quad had been built to a 426 for 2 years when i bought it.

I tore it apart to find out it had a wiseco piston in it, and the bore was worn out, but the piston had minimal damage.

So instead of buying a new $150 piston and rings, i bought a new sleeve for $60 and new rings for $25 and had my sleeve board and it saved me some money..

But my point, the piston that is in my quad now is a 2 1/2 year old wiseco piston that has shown me some great durability, and it hasnt done me wrong, so my vote is going to keep being wiseco.

Im also not much of a cast piston fan like namura is, from what i have read on them they have troubles with the crown cracking, etc and i dont want to take the chance with my quad, since it is a higher performance engine.

This artical may help you on your choice of piston type you choose.

http://www.motorcycleproject.com/motorcycle/text/cows-pistons.html

[05DodgeDakota]

I don't think you can go wrong between wiseco, JE, and CP. I think next time around when I decide to go extreme it's gonna be a CP. They are some Heavy-friggin duty pistons. There is a reason NASCAR trusts them.

[250x_kyle]

Originally posted by crownandmonster
I have always ran Wiseco or JE in my powersports and I have never had a piston/ring related failure with many hours on the pistons. We always run JE pistons in our dirt track motors (small block chevys), again again have never had a piston or ring related problem. They Also seem to stand up to heat a tad better as we can run them a bit leaner to get the most power out of them with the JE's as compared to something like a speed pro. You can always tell when the cheaper pistons have been run lean as they have pitting on top of the piston where it is literally buring a hole through the top of it.


An 11:1 wiseco with stock 400ex gaskets is going land you somewhere around a 10.5 CR. Throw a STG 2 HC on top of that and you might get away with your 3 degree key. I would have to stick with CJM on this though and recommend a 10:1 piston and 407 bore for your wants/needs.

agreed on the JE part. Ran one in my trx450r. and we also run them in small block modifieds and run them a tad lean for the most power. never had an issue with ring failure either.

we had a small block chevy that ran high rpms for two racing seasons with no issues. crank gave out one night breaking in three peices letting two rods go threw the block and still only had to replace the two pistons that went threw the block.

[400exrip]

I have been running Wiseco pistons in my bikes for 3 years now, Never had an issue with them at all, Highly recommend using them.

The New Moose racing pistons are made by CP Pistons, I have never ran J.E. Pistons, But I know a couple people who do and they have had great results with them also.

[caseywoods5]

Wiseco is the best because they are forged rather than cast. cast has a tendency to be weaker and expand/contract more when heated/cooled. forged is stronger and does not expand/contract as much. plus wiseco pistons are precision made for the best performance and they're the best bang for your buck. i've also heard JE pistons are great but don't know anything about them.

[JOHNDOE83]

Every motor Ive ever rebuilt has had a weisco replacement.

I never once had any issues with a wiesco piston in any machine I put it in.

Thats the only basis I have for a recomendation, my main reason is my 440, Ive done things that I thought would have been hell on my piston and rings and its held up for 6 years with MX and drag strip abuse and its never even lost compression.

Id think the 416 would last just as long if not longer.

weisco for me always.

[powerbomb400]

When I rebuilt mine I had the same frame of mins as you tri5ron. I put a Wiseco 88mm in with a 10.1 to 1compression. Didn't want to put alot of stress on the head. Had 17,000 plus miles when it was time to rebuild. Its nothing for us to be 20 miles from the trailers. To be honest I wouldn't done it any different. When it comes to the piston,rings and the head I wouldn't go cheap. I put the things in that are proven. With lower compression used Honda valves, seals, and gaskets. Already had a Stage 2 Hot Cam in so that wasn't a problem. I change my oil every 25 to 30 running hours depending on the season's so there wasn't no wear on the cam. I guess I've said enough but I believe you will get what you know that you need to do it right.

[01boneless]

wiseco here to but in my 450 im gonna try a JE to see what its like

[mlabarca240]

Ive heard JE pistons run well. Ive only had experience with wiseco's all my life. We run them in our bracket mustang, my quad, my fathers quad, hell, even in my ford ranger. Im running a 400ex 406 overbore, stage 1 HC, +3 degree timing key, and the normal pipe filter and jet setup. The bike is a torque monster. My suggestion however is take the sleeve/jug to someone who has bored sleeves or blocks specifically for wisecos on a regular basis. The pistons like a close tolerance bore or they get a little noisy. Ive never had a problem with them and I love them. They look great and they last forever.

[smithersusmc]

I have run JE pistons for 3 years. I had one engine blow due to a plugged oil line. The piston was almost undamaged. The rings did not hold up. I rebuilt my topend(same bottom) with a new piston and did not find my oil screen plugged until I started it. I ran that piston for 2 years running GNCC and Hare scrambles with no problem. I tore down my top end this off season due to a leaking base gasket and saw some of the same oil starvation damage from the initial start up. The quad had great power for 2 years with damage. I had the quad pinned on the rev limiter numerous times during races and never had a single problem. We used JE pistons when I worked at a machine shop in Texas. We raced them in all our dirt track cars. I have never had an issue with one of their pistons.
My quad is a 416 with stock head studs and cam chain. I ran 110 octane for the cooling purposes. Airbox with UNI filter and EHS lid. Choke removed from carb 42 pilot, stock needle, and 152 main jet. Full Yoshimura Exhaust. Stage 2 Hotcam. Motor was bullet proof.
It is worth the money for JE. I have seen that Wiseco holds up just as well. I have never used them though.

Hope this helps.

David

[250x_kyle]

well ron heres some proof of the small block that was running JE's only two pistons that were replaced were the ones the rods decided to sent thre the block when the crank broke. the old ones were re ringed and have about 5 races on since.

http://i46.photobucket.com/albums/f134/needanewquad/motor-1.jpg

[maddmaxxx]

-weisco are pretty good for dirt bikes...we call them seizeco in the harley business

-i have good biker buddies that work at dart head co. and ET performance...they will not use anything but JE

-ill be oversizing one of my 400ex's and ill blow the extra coin on JE

-even tho i just putz around on the farm ...im certain that weisco would hold up even in competition TOO


-those two co,s are the only pistons that are worth my time to in stall ON QUADS

-pS;i do use keith black hyperutectic on mild street harleys but for hi output street engines motor car/harley...=JE

-BUY A GOOD , WELL KNOWN PISTON...its not worth reboring your cyl. and then buying the better piston

-just my 2 bits