Pistons : JE or Weisco ?

[hondaexryda]

hey, im thinking of getting Sparks 416 kit, should i get JE Piston 12:1 or Weisco Piston 11:1 ? whats the difference ? or the better one......

[member]

id get the je, because they seem to be more reliable and thier compression ratios are more accurate then the weisco ratios are, but with the Je you will need to run a high octane fuel like a mix of race gas and 93 pump

[Glamis400ex]

Do a search, this has been covered EXTENSIVELY on here many times.

Glamis

[xc400ex]

Yeah JE's are much better than Wiseco and you will notice a greater power increase with JE. If you get a wiseco 11:1 comp its actually only about 10:1.

[hondaexryda]

ya, im probably going to order Sparks .. 416 Kit Sparks 416 Kit (http://www.sparksracing.com/Sparks_Center/400X/Sparks_416_gncc_kit.htm)

[416mx]

Colby at C&D Racing said the JE was a much better piston. I ordered a 426 piston from him,11:1 comp.::macho :macho :macho

[Silverfox@C&DRacing]

That is right I only use JE or ROSS piston they are alot better pistons. This is all I put in my 416,426,or440 kits:)

[sandspanker]

what does a je piston cost from c&d i am eventully going to gowith a 416 piston;) :p

[Glamis400ex]

call the number on top.

Glamis

[Dunlap]

Originally posted by Silverfox@C&DRacing
That is right I only use JE or ROSS piston they are alot better pistons. This is all I put in my 416,426,or440 kits:)

If you make a statement like this please tell us exactly why you think this.

[Steve-o 400EX]

Yea definately go with the JE, thats what I got in my 416. hondaexryda, It might be cheaper if you piece together your own 416 from C&D racing. Also with a 12:1 piston you will have to run race gas without a doubt which costs $35 per 5 gallons in my area, not sure what it is where u live. Unless ur doin some serious racing i would go with the JE 10.8 piston, thats what I have and it runs awesome. Check my sig for other mods and if you have any other questions let me know.

[dirtmomma]

We havne't had ANY problems w/ our Wiseco pistons, we've had one inour blaster for the last year & it's got 2 seasons of flattrack racing on it & is still running STRONG I just put a high compression one in my 300 & haven't had a problem either & we're getting ready to do a 460 kit :eek: on our 400 w/ Wiseco parts!! I think all the talk about Wiseco now everyone thinks they are not good parts but like I said we use them in ALL of our teams race quads nobodys kacked one!!!

[Steve-o 400EX]

Originally posted by dirtmomma
We havne't had ANY problems w/ our Wiseco pistons, we've had one inour blaster for the last year & it's got 2 seasons of flattrack racing on it & is still running STRONG I just put a high compression one in my 300 & haven't had a problem either & we're getting ready to do a 460 kit :eek: on our 400 w/ Wiseco parts!! I think all the talk about Wiseco now everyone thinks they are not good parts but like I said we use them in ALL of our teams race quads nobodys kacked one!!!

We are not saying that they are bad, we are saying that JE and Ross are better. Wiseco's big bore compression ratio's are not what they are claimed to be either and that is a proven fact. So basically ur sacraficing power, try a JE or Ross and you'll know the difference.

[ajr400ex]

I am looking into having my 400 engine built as well. I find it interesting that most engine builders I have talked with use Wiseco. They do this every day for a living so I would have to think there is a reason for this.

I believe the only differences between the 2 is the weight and the actuall TRUE compression.

Mickey enlighten us regaurding the differences...:D

I believe what should be said is that Weisco makes a good piston, they've been around forever and for good reason. There are many motors running around with Weisco's in them and do just fine.
After discussing options for my motor with an engine specialist who builds both race bikes and race car engines for levels up to the Indycar series is that they prefer to use JE Pistons on their applications where exotic setups aren't required. They agree that Weisco makes a good product but you can do better with the JE or Ross setups.

[brandonpeake]

well i know im looking into a 416 and gt thunder,laz reccomended wiseco and ill prob go with that, i know he told me he's never had a problem with them and i would think he definitely knows more than me on the matter

[Dunlap]

My point is there is no difference. All the pistons don't have the right deck hieght, therefore the compression ratio are all wrong. There is no difference in quality but some may look better. The rings on JE and Wiseco are the same, so what is the difference? Iam not on here supporting one or the other and contrary to popular belief I'am not here to fight with anyone but if you make a statement that one is better than the other tell us why.

[dirtmomma]

Originally posted by Steve-o 400EX
We are not saying that they are bad, we are saying that JE and Ross are better. Wiseco's big bore compression ratio's are not what they are claimed to be either and that is a proven fact. So basically ur sacraficing power, try a JE or Ross and you'll know the difference.


Well I thought I heard that they were working thru this problem;) I'll just stick w/ Wiseco since I get good discounts:D my brohter in law in a Wiseco dealer so it's all good!!!

[member]

ok what do the numbers in the compression ration mean? like in 11:1 what does the 11 stand for and what does the 1 stand for??

[F-16Guy]

There is nothing wrong with Wiseco. Wiseco and JE merged in June of 1999, forming Performance Motorsports Inc. Although they operate independantly, each company shares the best operating and production practices with the other, essentially assuring that their product is the same. After the merger, PMI also acuired Vertex Pistons in September of 2000 and Carrillo Industries in July of 2001, so is the quality of their products in question also?. Like Mr. Dunlap said, the deck height is the same; I'm willing to bet the quality standards and all other aspects are the same also. I can't speak for Ross because I haven't had any experience with them, but aside from weight, I'm guessing they're pretty close to Wiseco's demensions. The bottom line is this; if you want an exact 11:1 or 12:1 CR, take the measurements, do the math, and make the adjustments to obtain it. If you can't, pay someone who can.

Well said Micky and F-16guy! I had a Weisco in my old 3-wheeler for years with no problems. And it's absolutely true that the "Real" compression numbers will be accomplished by a competent engine builder. Remember too that when people talk about weight of a piston, the more it is lighter or heavier it is vs. stock the more you will need to look into balancing the crank, otherwise your engine will vibrate more. When my friend did his bike he lightened the piston as much as was possible and then had to balance the crank to reduce the buzz. I may be wrong on this, could you please reply to this Mickey? There already is enough misinfo out here, I don't want to add to it! :)

[KASCHAK]

Originally posted by member
ok what do the numbers in the compression ration mean? like in 11:1 what does the 11 stand for and what does the 1 stand for??

ok in the figure 11:1 the 11 means when the spark is fired and the piston is all the way up. the compression inside is 11 times more then 1 or down or outside the motor. so the higher the first number the more compression or force behind it

[chad502ex]

forged vs. billet

[chrisp333]

i use a wiseco 416 and have no problems at all. je and ross are fine but all the negative sh*t that you hear about wiseco is a myth or it is now. the problems they had were for 2 strokes anyway. a 400ex is a four stroke... just my .02

[YZROOSTINYA]

compression

entire cylinder volume+ head volume / head volume

say 250cc + 20cc / 20 = 13.5:1 compression ratio. I think that is how it works

I also think to get a TRUE 10.8:1 with any 416 kit you need to get rid of the base gasket and run only 1 sheet from the 3 peice headgasket.

Not 100% though.

or deck the cylinder .030"

[Dunlap]

Originally posted by mrbluehair
Well said Micky and F-16guy! I had a Weisco in my old 3-wheeler for years with no problems. And it's absolutely true that the "Real" compression numbers will be accomplished by a competent engine builder. Remember too that when people talk about weight of a piston, the more it is lighter or heavier it is vs. stock the more you will need to look into balancing the crank, otherwise your engine will vibrate more. When my friend did his bike he lightened the piston as much as was possible and then had to balance the crank to reduce the buzz. I may be wrong on this, could you please reply to this Mickey? There already is enough misinfo out here, I don't want to add to it! :)

Balancing on a counter-balanced motor is not as crucial and I really don't get into balancing single cylinder motors - I have found that it hasn't been worth the time and money. I do keep it in mind when I build a motor with a big stroke though. When we do the 500EX, I use a lighter rod/bearing and pin for the bottom end of it along with a lighter piston than stock and the only vibration you feel is going from a 400cc motor to a 500cc motor. There is a lot of misinformation on these forums and that is the only reason I get on here. I am not trying to sell anyone anything or start any trouble but when I see something that is just thrown out there with no basis, I have to say something.

[Steve-o 400EX]

Originally posted by chrisp333
i use a wiseco 416 and have no problems at all. je and ross are fine but all the negative sh*t that you hear about wiseco is a myth or it is now. the problems they had were for 2 strokes anyway. a 400ex is a four stroke... just my .02

I dont know about 2 strokes but if you read through the threads most of the complaints about the wiseco pistons were guys with 440 kits on their ex's. Also JE and Wiseco pistons are merged but the are NOT the same. Look at them both and there are differences.

[YZROOSTINYA]

my buddy has a stock bore 400 at 11:1 with a wiseco. has about 500-600 hours on it. this is after the 150 stock hours he put on it.


its a 99 and still runnin strong. I ran wiseco in my dirtbikes years back. never had a problem.

Not so much as the kits were advertised wrong as the people building them dont know what there doing.

there are so many factors that go into a correctly built motor that you have to generalize in some cases

[Dunlap]

Originally posted by Steve-o 400EX
I dont know about 2 strokes but if you read through the threads most of the complaints about the wiseco pistons were guys with 440 kits on their ex's. Also JE and Wiseco pistons are merged but the are NOT the same. Look at them both and there are differences.

Then what is the difference"looks only"! That is the only problem, no one ever gives an answer. The only problems with ANY 440 kit is that poeple don't relieve the cases towards the back of the cyl. and when the sleeve and cases exspand they touch. Then the piston gets pinched and it scuffs. Maybe the only ones you read about on here where Wisecos, but I see it on almost every cyl. that come through here.

[Steve-o 400EX]

Dude, dont go into cardiac arrest over it, its gunna be okay. I'm just sayin what have have read on some of the posts, i'm not on here 24-7 like most people are, i got better stuff to do. But from what it know, wiseco pistons are good, but i have learned that JE and Ross are a littel better becuase they are lighter which enables the motor to rev quicker which would mean they are better than wiseco.

[Dunlap]

Originally posted by Steve-o 400EX
Dude, dont go into cardiac arrest over it, its gunna be okay. I'm just sayin what have have read on some of the posts, i'm not on here 24-7 like most people are, i got better stuff to do. But from what it know, wiseco pistons are good, but i have learned that JE and Ross are a littel better becuase they are lighter which enables the motor to rev quicker which would mean they are better than wiseco.

I'll be fine don't worry. But you are basing what you think you know on what you heard on here which means you are misinformed and you a relying on unrelyable info and that's all I'am trying to say. This is not me being arrogant or self righteous I'am just trying to help. I'am not trying to change the world just trying to give the best info to the poeple that will listen.

[brandonpeake]

well i think mickey would know more about this than anyone else on here, this is what he does everyday, just my opinion, want to know about pistons ask an engine builder

[brandonpeake]

well i think mickey would know more about this than anyone else on here, this is what he does everyday, just my opinion, want to know about pistons ask an engine builder

[brandonpeake]

well i think mickey would know more about this than anyone else on here, this is what he does everyday, just my opinion, want to know about pistons ask an engine builder

[Bill Fuller]

Why would anyone argue with Mickey?I for one am proud to have an expert of your caliber on the site Mickey.And for those of you who don't know who Mickey Dunlap is than talk with someone about the history of ATC's and ATV's and you will realize how lucky we are to have him on this site.

[86atc250r]

I've weighed all 3 major piston players (and stock) on a scale accurate to 0.1 grams (cut a paperclip into 10 pieces & it could recognise one of those pieces).

I weighed them piston alone, and as an assembly.

The Ross is by far the lightest of the 3 (either 87mm or 89mm) and most closely matches stock...

What does this mean? Power? Vibration?

Well, I doubt it will have a significant effect on power. Additional vibration may be an issue with a significantly heavier (or lighter) piston, but the effect should be minimal.

My biggest concern about these pistons is matching stock as closely as possible for a couple reasons (possible additional vibration being one) - the other and more siginficant reason is stress on the connecting rod.

As the piston approaches TDC on the exhaust stroke it must immediately change directions and has little to no resistance against it (like it does on the compression stroke). At this point the rod has tremendous stretching forces against it as it stops the piston and pulls it back down toward BDC.

Any mass you add to the piston adds force against the rod. At high RPMs this can be the difference between breaking your rod and not breaking it.

Another factor to consider when choosing a piston is dome shape. Wiseco pistons use a dome that is flat on top (good), but has sharp edges as it tapers down (bad). This is bad because sharp edges make the engine more prone to detonation. Ross and JE pistons use rounded domes without sharp edges.

Other differences in these pistons are more just FYI than anything - the wrist pins - Wiseco uses a tapered wrist pin that is lighter weight (like stock) so that their piston can be heavier, but the whole assembly ends up roughly the same as a JE piston (that uses a non-tapered wrist pin).

The Ross also uses a non-tapered wrist pin, but is ends up significantly lighter than either the Wiseco or JE. Ross also offers a couple wrist pin options and associated costs.

Oiling is a little different in each of these pistons, but I can't really comment much on that.

None of the above pistons are known for failing, so that should not be an issue for anyone.

Some engine builders don't like using Ross pistons because their rings are not "pre-gapped" & require a little extra work to gap them correctly.

In the end, the thing to remember is like Mickey said, the differences in these pistons is relatively small and all are quality parts. For most people, the piston they run will make little real world difference...

[QuadJunkies]

Glad to have you here to explain all this Mickey~~
I just got a Ross piston(reccommended as the best) There is alot of good info o nthe site AND a little mis info I think as well.. I recived a few emails from some trying to help me get the right Bore kit for my quad,and Im glad I did ALOT of homework first...Ive learned a ton from people here o nthe site, buts its ni.ce to get someone like you with Extensive background to help educate us all.........:)

[Dunlap]

Originally posted by 86atc250r
I've weighed all 3 major piston players (and stock) on a scale accurate to 0.1 grams (cut a paperclip into 10 pieces & it could recognise one of those pieces).

I weighed them piston alone, and as an assembly.

The Ross is by far the lightest of the 3 (either 87mm or 89mm) and most closely matches stock...

What does this mean? Power? Vibration?

Well, I doubt it will have a significant effect on power. Additional vibration may be an issue with a significantly heavier (or lighter) piston, but the effect should be minimal.

My biggest concern about these pistons is matching stock as closely as possible for a couple reasons (possible additional vibration being one) - the other and more siginficant reason is stress on the connecting rod.

As the piston approaches TDC on the exhaust stroke it must immediately change directions and has little to no resistance against it (like it does on the compression stroke). At this point the rod has tremendous stretching forces against it as it stops the piston and pulls it back down toward BDC.

Any mass you add to the piston adds force against the rod. At high RPMs this can be the difference between breaking your rod and not breaking it.

Another factor to consider when choosing a piston is dome shape. Wiseco pistons use a dome that is flat on top (good), but has sharp edges as it tapers down (bad). This is bad because sharp edges make the engine more prone to detonation. Ross and JE pistons use rounded domes without sharp edges.

Other differences in these pistons are more just FYI than anything - the wrist pins - Wiseco uses a tapered wrist pin that is lighter weight (like stock) so that their piston can be heavier, but the whole assembly ends up roughly the same as a JE piston (that uses a non-tapered wrist pin).

The Ross also uses a non-tapered wrist pin, but is ends up significantly lighter than either the Wiseco or JE. Ross also offers a couple wrist pin options and associated costs.

Oiling is a little different in each of these pistons, but I can't really comment much on that.

None of the above pistons are known for failing, so that should not be an issue for anyone.

Some engine builders don't like using Ross pistons because their rings are not "pre-gapped" & require a little extra work to gap them correctly.

In the end, the thing to remember is like Mickey said, the differences in these pistons is relatively small and all are quality parts. For most people, the piston they run will make little real world difference...

Now that was a good answer!

[F-16Guy]

Originally posted by Mickey Dunlap
Now that was a good answer!
Amen.

I enjoy intellectual insight.

Since I am doing my motor this summer the more info I have the more I look forward to the improvements. The person building my engine is in his early 20's but has a wealth of knowledge and respect for the internal combustion engine that makes his work much older than his age allows.
The reason I borught up the vibration question and this tells me even more about his abilities is the first quad motor he did was a 230 quadsport built to 270, lectron carb, webcam and hand built exhaust on alcohol. This was almost electric smooth because the piston had been lightened and vibrated bad till he balanced the unit to the point where it almost seemed TOO smooth. Now he does machine and engine work on Indy Cars so I feel I will have somthing to tick off guys on the new 450's with.
Thanks again for all the great info, and for those who don't know, Mickey is the man, anyone who can not only finish, but WIN the baja 1000 on a 250r THREE WHEELER demands mass respect!

[YZROOSTINYA]

Originally posted by Mickey Dunlap
I'll be fine don't worry. But you are basing what you think you know on what you heard on here which means you are misinformed and you a relying on unrelyable info and that's all I'am trying to say. This is not me being arrogant or self righteous I'am just trying to help. I'am not trying to change the world just trying to give the best info to the poeple that will listen.


exactly:)

can you pm on how to get a TRUE 10.8:1 with the JE.

[Dunlap]

The only way to truly find out what compression ratio you have is to put the motor at top dead center, fully assembled with the spark plug out. You will need a syringe that will hold at least 60 cc's. You can use a nice 10:40 motor oil or fluid of your choice. Have the motor so the piston will be completely vertical, fill the combustion chamber with oil, rock the motor around, leaning it forward, backward, right and left to make sure there are no air bubbles. If you had a 440cc motor, it would take 44cc's to make 11:1 or you take the size of the motor (440) + 44 (for the cc amount) divided by 44 (the cc amount) will equal 11:1. If you have a 416, you will need 41.6cc's to make 11:1. I hope that is clear enough. To find out exactly what compression ratio your piston has, this is what you would do. On a 400EX, you can leave the base gasket off which is .020 thick and this will raise your compression ratio up quite a bit. If you need more compression take off 2 pieces of your 3 piece head gasket, coat it with a heat temp paint and this will actually give you the best quench area and will build the best power even if you are only at 10:1. Matching compression ratios with cams, lifts, durations and lobe centers all take a lot of work - also known as R&D.

[Doibugu2]

Mickey how important is the head cover gasket. I know it doesn't have anything to do with compression. But does it need to be changed everytime you take the head off?

[Dunlap]

Originally posted by Doibugu2
Mickey how important is the head cover gasket. I know it doesn't have anything to do with compression. But does it need to be changed everytime you take the head off?

I use them over two or three times. If the black stuff comes off and you had to use it you can clean both the gasket and the cover and head surface good with acetone and paint the gasket with krylon bar-b-q paint.

[Doibugu2]

cool thanks

[JOEX]

Mickey and Gabe (86atc250r),

I too, am glad you guys are here to help clear up some of the misinformation. I always have an eye out your posts.:)

Joe

[sandspanker]

:D I too am glad that everyone is on exriders. when it comes down to it it is just personal prefance on what piston the person wants to use. Their all good. just my .02 cents:p

[YZROOSTINYA]

thanks.

I am looking to do some work to my kit to make it "right" in a sense.

In a month or two.


We are all guilty of hear say every now and again. I have a hard enough time remembering what is right and when I am wrong. The latter seems to hold true TOO often:huh

[Steve-o 400EX]

Originally posted by Mickey Dunlap
I'll be fine don't worry. But you are basing what you think you know on what you heard on here which means you are misinformed and you a relying on unrelyable info and that's all I'am trying to say. This is not me being arrogant or self righteous I'am just trying to help. I'am not trying to change the world just trying to give the best info to the poeple that will listen.

I wont disagree with you there. Yes there is a bit of wrong info on this site and I could have caught wind of some of it or just misinterpreted it. I am just sayin what i have read.