total cc'

[robyone]

hey guys, I usually don't post on here but r riders is down right now and I have a ? I have a 88' 250r motor that is bored 1mm over with a 18cc dome coolhead, my ? is what is my total displacement (cc) if any of the 2 stroke guys could help that would be great! thanks ...Roby

[ESR350r]

Your dome does not matter on displacment because displacement has to do with the bore and the stroke. Your clearance volume and your dome cc has to do with your compression ratio. The equation to calculate your displacment is: (3.14/4) x (bore^2) x (stroke) then take all that divided by 1000. The stock bore is 66mm and the stock stroke is 72mm. So your total cubic centimeters right now is 253cc. The stoke motor displacement is 246cc. I hope that helps.

[robyone]

thanks esr350r, thats exactly what I needed to know! I wasn't sure about the dome effecting total cc or not. I'm planning on getting a esr310 in the spring, I've heard that the bigger bore motors,330 and 350 chew through clutches like crazy. how long does a clutch last in your motor? thanks again...Roby

[ZRider400]

if your curious about any other sizes...and what CC's it is. i made this bore chart

http://www.**********.net/BORECHARTpage.htm

[ESR350r]

I have had my motor since the middle of the summer. I had the stock clutch basket in when i got it and it was already bad so i upgraded to a hison clutch basket and heavy duty clutch kit in late in the summer. Since I drag race, hill climb, and XC race i slip the clutch alot, but i have not noticed any problems yet, i change my oil alot in hopes that that will prolong my clutch life. I know that the big bores go through clutched more because of the increased power but i have not had any problems yet. Buying new clutch plates is a small price i am willing to pay for more power. $76 for new plates is not too much, I have that much in 6 gallons of gas. The life of the clutch all depends on how much you ride and how you ride. I try to ride alot and as hard as possible. I would be happy to get a two years out of a set of clutch plates. I hope that helps

[robyone]

2 years wow , the way it was explained to me , they went through a clutch in like 10 or so hours. even if you get a year, it would be worth the 76.00 , may be I will get the 330 then. thanks for the info esr350r and z400....Roby

[ESR350r]

I ran the last hillclimb for the state championship in Indiana, the ironman GNCC race in crawfordsville and another harescramble in southern Indiana, along with running the piss out of my quad dragging with friends and play riding, and i know for sure i have more then 10 hours on it, and i know my clutch is still good. I would also be happy with getting a year out of it, but so far i can see going till next year till i get a new one but i am not 100% sure. It is nice to hear you are going with an ESR motor. Make sure you ask some questions or do research on the motor before you get it. It will take some $$ to bore the cases and get a bigger carb. It is not just getting the 330 kit and bolting it on. I would also suggest getting a powervalve motor if you have the money. It all depends on what you wnat to do. Feel free to ask my any questions, i will try my best to help you out.

[robyone]

ya! esr for sure, I 've been rebuilding my R since april and looking into motor options and from what everyone says, esr is the way to go, reliability, quality and awesome customer service. I'm going to rebuild my bottom end this winter to get it ready for the new top end in the spring. I was going to get the 310 pv but I don't know now I might want the 330pv. how about cooling, do you have an over size radiator? that was another reason I was only going with the 310. I've read that the 330's and 350's get up in the 200 degree range, ever have over heating problems?

[ESR350r]

Yep, I had and still have some serious heat problems. At fist my fmf pipe was on my radiator hose line and it was getting hot but i did not know how bad it was, then i got the ESR temp gauge and saw it was pretty bad. So i got my pipe of the line and it would run a decent temp but it would get over 200 in the woods but as soon as i hit the road and opened it up it would drop below 175. I am running a stock radiator with water wetter right now. When I ran the ironman and the last hare scramble it would got crazy hot like over 250. I was scared but it never blew up. I had steam coming out of my overflow 5 minutes into the ironman and i still ran the rest of the race. ESR said it should operate around 205 degrees in normal riding so that is what i base my concerns off of. There are after market radiators for $250-$300. I talked to ESR about it and then have 2 center mount pipes that do not have much of a stinger and running those are the same as having an over sized radiator. They cost aout $350 for a pipe and silencer and it increases perforamance. To run that pipe you cannot have an airbox which is not a problem for me because i will keep the pipe i have now so i can still run my air box when it is wet. So i am going to get that pipe this winter and see how things go and if i still need the over sized radiator i will get that but i am going to try the pipe first. I would strongly suggest the $80 temp gauge regaurdless so you can keep an eye on it. It depends on what you are going to do when you get the motor. Let me knwo what you are planning to do and i will give you my opinion. Also on the bottom end if you get the stroker crank and a 330 kit you will be at 350cc. the stroker crank is when you have to machine the cases. who are you gonna have do your bottom end?

[robyone]

over 250! man that sounds really high, I would have been so scared of blowing that expensive motor. the guys that have the big radiators say they run around 180 degrees normally and 200+ when hot. but if esr said 205 is normal then thats not so so bad. have you tried engine ice yet ? ,I used to over heat after riding really hard but since using engine ice it hasn't over heated. running no air box really isn't an option for me, so I'll be heading the over size radiator route. a stroked 310 is starting to sound pretty good , I talked to a guy with a 310 and a stock radiator and he has never had any over heating problems, everyone that has the 330 has them. plus you don't have to machine the cases for the 310. do you know if you need to machine the cases for the 4mm crank? well if I get the stroker crank I 'll send it to esr to have my bottom end done if not, between my clymer manaul and my 250r cd rom I think I can handle it. I need new cases and I 'm worried that if I don't replace my tranny, somewhere down the road the infamous 2nd gear explosion will get me and ruin my new cases. so I'm looking at like 500.00 for cases 500.00 for a stroker crank 1600.00 for the pv. and a tranny,which I haven't checked the price on yet and all the misc. seals and bearings. I think what I 'm going to do is send the bottom end to esr, have them put in the stroker crank and inspect everything and tell me if I need a new tranny or not. and just roll my top end with spacer plate till I have enough money for the 310pv. since the 310 doesn't require case machineing and I can just slap it on my self when I get it.