DOODS, I did something stupid!!

[beerock]

I know this isnt a 250r forum but a honda is a honda.

anywhooo.....

I ordered all the parts to put my 250r back together.

The engine is heavily modified it has a 88 cylinder with a *86 spacer plate* and a 86 piston._ (I lost the number to the engine builder but this morning I realized I ordered the wrong piston)
the reason the 86 piston and spacer plate is used is so the crank case has more volume and in turns creates a wider powerband.

well, I bought a 88 piston i cant use the 86 motor spacer plate and my powerband will be more abrupt and not as smooth(thats the opposite of what a wide power band is).

So I have a dilemma of either waiting for the 86 piston (which will take until wednesday to get) or using the 88 piston I got and perhaps losing some power.

what should I do???

should I just put it together with out the spacer plate and run it for like 20 hours and then put a 86 piston in there with the 86 spacer??

Im not sure how much power I will lose if I do it, i guess it could be a good learning experience.

oh by the way, I want to get my quad running before my friends come down to come riding with me.

If i wait fot he 86 piston, I will pretty much have to pray that it will start up when I throw it in the frame. So me andmy buddies can go riding.


what should I do?

[Guy400]

Maybe I'm confused but what does crank case volume have to do with your powerband? Also, a cylinder spacer won't change the volume of your crank case at all. I think you're referring to cylinder volume and a cylinder spacer will affect the volume of this. I don't know about the 250R motor but if the 86 spacer is thicker and you don't compensate by increasing the stroke or milling the head, etc. you're going to lose power. Conversely, if the 86 spacer is thinner you'll make more power but you've got to check piston to head clearance.

[Leo]

http://www.macdizzy.com

TONS of great R specific and general 2-stroke info.

Leo

[beerock]

hahaha, hey guy 660r, the spacer DOES give more crankcase volume, and in turn it gives a wider powerband andsmoother power delivery.

the 88 piston has the wrist pin 5mm higher then the 86 piston (87-89 pistons had a wristpin raise of 5mm )

I dont want to sound rude but if you dont think a motor spacer wont give more crank case volume then keep doing what your doing, riding a YAMAHA

YA YAMAHAS IS GA'BAGE!!!!!!!

[Guy400]

Look, I said in my first post that maybe I don't understand what you're trying to ask us and I hope this doesn't turn into a thread where people are taking sophmoric stabs at each other (like you're apparently doing).

I don't want to sound rude to you but maybe you don't know a whole lot about the internal combustion motor. The crank case and it's volume has NOTHING to do with your powerband. I think you're confusing the crank case with the cylinder. The crank case is the lower part of the motor where, obviously, the crank sits along with the clutch, trans, etc. and holds the oil. Given your theory of the crank case volume effecting the powerband you're telling me that if I add or remove a certain quantity of oil that your powerband is effected? After all, if you overfill or drain oil from your crank case it's going to change it's internal volume. Hmm, I'll have to ask other 2-strokers if they notice where and how hard their powerband hits when the oil gets low?? :huh

As I said in my first post, changing the cylinder volume will have an effect on where and how hard the powerband comes on. In your original post you said you got the wrong spacer for the cylinder and that's what I responded to. I was just trying to understand what you were asking so as to help you better. If you don't appreciate the help, that's fine. Just go on and port your crank case to help out that powerband...

[Guy400]

This is the crank case, is this the part you're talking about?
Left view:

[Guy400]

The right view:

[Guy400]

And the actual crankcase itself:

[AlaskaSpeed]

Guy660,
I think your (and my) understanding of the internal combustion engine are correct. However; I did notice a slight powerband modulation when some chain lube flew up into my eye, causing me to let off on the throttle to wipe it out. :p JIM

[beerock]

Excuse me guy 660r and alaska YOU ARE WRONG!!!!!!

first off its a two stroke, and the spacer plate DOES effect crankcase volume. It goes between the crankcase and the cylinder



IT DOES effects the powerband.

[quadfamily]

Guy660R,
Try to leave this one alone to avoid more trouble. Your intentions in trying to help are good. I know you know what you're talking about with 4 strokes but the 2 strokes are totally different animals. In a 2 stroke the is NO OIL in the crankcase. The fuel from the carb goes directly into the crankcase (yes the crankcase)on the UP-stroke of the piston ( I know this sounds backwards!). This is why you mix oil with the gas in a 2 stroke. The oil in the gas lubricates the crank bearings and the cylinder wall. When the piston goes down it creates pressure inside the crankcase and forces the air fuel mixture into the cylinder ABOVE the piston through what's calles a port which is a passage between the crankcase and the cylinder. There are no valves or cams in a 2 stroke motor. In the 2 stroke engine little tricks like the cylinder spacers and reed spacers add volume to the crankcase and therefore let more air fuel mixture into the crankcase and can make serious differences in power and where the power comes on in the rpm range. Also the exhaust pipe on a 2 stroke motor is very critical for power delivery. You can change the whole way the engine runs by changing to a pipe with a different shape, size and length of expansion chamber. 2 Stroke power is a whole science in it's own and has nothing to do with 4 stroke technology. Instead of picking on each other here lets explain what we're talking about better. Guy660R obviously doesn't realize how different 2 strokes are. Hopefully this will help.

[NJ250Rrider]

86 spacer plate??? Never heard of it. A spacer plate is used to run an 86/cr piston on a long rod crank.

[stocktires]

nj, ur right, there is no 86 spacer, its an aftermarket spacer for running an 86 piston and 87-89 rod, and it DOES increse crank volume!!! this is an add from NAC'S RACING!!!

CYLINDER SPACER PLATE
Increases crankcase volume on TRX250R 87-89 motors. Requires use of CR or '86 style 250R piston, long stud & dowel kit, and an extra base gasket.
Part # NC110 $39.95

THERE!!! ITS FINAL IT DOES INCREASE CRANK VOLUME!


-I LUV 2-STROKES-

[stocktires]

BEEROCK,
I'd go ahead and get the 89 piston if you got money. But it wont make alot of difference but you will feel the difference in the power delivery. Many engine builders tell me the 87-89 rod, 86 piston, and spacer doesnt make a whole lot of difference on a small cc 2-stroke but the power difference is noticeable, i have to agree. But i like a strong 2-stroke HIT!!! I just use it to my advantage and FLY. it doesn;t wear me out much on the track cuz i got alota stamina. but its your decision!

[beerock]

yeah that sounds about what Im gonna have to do 1986 trx250r.
I love a strong hit on the power band, especially if I havent approached the jump fast enough.

well we shall see, because I do want the increase in crankcase volume. But I am going to experiment, im gonna run my new engine for 20 hours with the 88 iston, and as soon as that 20 hours comes up im gonna buy a new 86 piston wrist pin bearing Etc and throw it on with the plate and go ride and see if there is any noticable difference.

I know all of the guys at nacs racing use them. Because it increases the volume.

Hey guys, listen I was just trying to explain to guy660r what it did and he just kept telling me that I was wrong.

I dont know about you but It irratated me.

hey do you think it will be ok to change the pistons out without honing the cylinder?

[barbwire44]

ya im gonna have to agree with beerock the power will be affected, and a two-stroke engine does use the gas /oil mixture to lubricate the crank, the gear oil is used to lubricate the gears,That is why jet skis and some snowmobiles dont use gear oil in the crankcase....there aren't any gears and the fuel is used to lubricate the crank and bearings. Hey guy660 youre an old suzuki man remember the 85 quadracers you had to pull the jug to get to the reeds because they were in the lower part of the cylinder angling towards the crank. And alot of guys are using the spacer plate on the 250r's not only for performance but because of the avalability of the older cylinders from the atc250r's that ran the same cylinder with a shorter stroke.:D

[AlaskaSpeed]

Hey guys, listen I was just trying to explain to guy660r what it did and he just kept telling me that I was wrong. I dont know about you but It irratated me.

I dont want to sound rude but if you dont think a motor spacer wont give more crank case volume then keep doing what your doing, riding a YAMAHA YA YAMAHAS IS GA'BAGE!!!!!!!

If you look at the above posts, you will see that you didn't need to insult him to make your point. Hell, just tell him that you are getting irritated; at least that isn't insulting him. Anyways, your apology should be to Guy660r; not the rest of us. JIM

[stocktires]

Yea beerock,
you didnt have ta be like dat, i'm not a fan of yamaha's but hell, ya didnt have to insult him, actualy he's selling the raptor for a 400ex (maybe z400). So beerock play nice!

[beerock]

hey guys listen up. I will not apolpgize to guy660r ok? we already have an understanding.

I told him not to keep it up, but he did.

i'm not being a either.

My intelligence was being insulted, why the **** is this turning around on me?

I was right. LEAVE ME ALONE ABOUT IT!!

Oh and I do not like yamahas, Ive always ridden RED since I was 8 years old.

Ill never buy a yamaha.

I can have my opinion. and my opinion is ya yamhas is ga'bage!

[stocktires]

WELL, you were right so i guess you can go and say just whatever the **** you want!!! not, that was a remark (sry leo) but he is being like TOOL (sry tool) was when he first got on the forum!!! He thinks he knows everything, he's has supreme intelligence, and were all idiots and should bow down to him. I respect guy660 and he's a nice guy, people make mistakes so beerock just kicked him whil he was down! o yea and beerock i understand you have an opinion about yamaha and there garbage buit i have an opinion about you and its your an ! So i guess my opinion is right cuz i was right about the spacer giving more crake volume too, RIGHT???? and i guess i wont apoligize to you cuz i was right too! I've never bought a yami either but that doesnt mean there crap so open up to some things kid. I'm just lettin off steam had ta get it out of me ya know! this is my last post to THIS forum.

[beerock]

thats right you can say whatever you want just remeber who started this topic.

I was trying to get advice about my engine setup and someone comes into the topic and tells me im wrong about something that I know .
I didnt want this to turn into a flame, I hate flames.

I am sorry for that.

I am not sorry for sticking up for myself.

this is my last post on this topic.

thanks for the help whoever helped me!

[stocktires]

i hate flames too but you got me pissed man! sorry for everything i said but Guy made a mistake!!!! everyone does!!!! its no big deal!!!! you just tought him something, thats good! thats what these forums are for (thanks leo) for us to learn from each other! its good you stuck up for yourself but you should have kept your opinion of yamie's r garbage to yourself. OK this is my last post on this forum, lol

[JabberJaw]

I AM SOFA KING WE TODD DEAD! :-)

[quadfamily]

You must be really bored Jabberjaw. This thread died on Nov 4th!

[JabberJaw]

It popped up on my "Today's New Posts' list?

Whew, I am glad finally sombody understands 2 strokes. Back to question. If you keep the same rings, you can get by without honning. Hense you don't have to break in the rings again. If you change the rings, hone the cylinder. The rings have to be able to seat to the cylinder in order for good compression.:(

[quadfamily]

did anyone understand my explanation on the first page? I hope so! Anyone disagree?

[9300EX]

never install a new piston and rings without at least running a hone through there a few times, just to break the glaze. even if it only has 20 hours on it:D

[beerock]

I never thought this topic would come back to light.

DIE!!!! topic!!

i am not sure, u might not hav to, casue its only 20 hours, but if u like it better, u will

[4punksdad]

beerock.......if you want to kill this topic, simply delete it. you started the thread, and you have the power to delete it. simply click the edit button under your first post, then check the delete box at the top of the screen.

[Leo]

I have to throw in my .02 cents....

Just adding the spacer does NOT change crankase volume... All it would do is change port timing, and lower the compression of the bike. Because the piston + stroke are the same, there is no change in crankase volume.. (if you want to get real picky the change in port timing may have a slight effect)..

Adding the spacer and changing the piston DOES increase crankase volume... simply because the piston is raised up in the bore.

This seems to be where all the confusion came from..? I don't know how this turned into a big war...?

If someone makes a post that you don't believe to be accurate, better to use facts, not insults to make your point...

..sigh..

Leo

[WwsivicwW]

Originally posted by Leo
http://www.macdizzy.com

TONS of great R specific and general 2-stroke info.

Leo

this is excellent!!!! thanks for sharing!!!!

[fmftrx300ex]

i know were suposed to all be kids at heart because we love to ride and all that but honostly how old r u guys dont start wining and insulting with "we'll yamahas are stupid" thats reduclous. do some researce b4 u have to prove someone wrong especialy if your not sure