LT 250r Quadracer cylinder differences

[hondaATCman]

I was wondering which type of cylinder had the best performance such as port timing, etc...the '87 or the '88+? I have the cylinder from an '87 on my quad right now but am thinking about switching to the '88 and up style because of the aftermarket parts compatibility, but I do not want to lose performance. So what's the difference? Thanks!!

[Wickedfinger]

There are alot of subtle differences between the '87 and '88 - '92 models. First off, the jugs are different and have different part numbers. The main differences lie mainly in a different intake and reed valve/cage arraingement - they will NOT interchange. The porting spec's and compression numbers are different and they also run different temperature plugs ('87 a B8EGV, '88 a B9EGV). Also the cranks and journals are different between the two.

[hondaATCman]

There are alot of subtle differences between the '87 and '88 - '92 models. First off, the jugs are different and have different part numbers. The main differences lie mainly in a different intake and reed valve/cage arraingement - they will NOT interchange. The porting spec's and compression numbers are different and they also run different temperature plugs ('87 a B8EGV, '88 a B9EGV). Also the cranks and journals are different between the two.

Yeah, I know the jugs are different, but they will bolt on to the '87 tranny cases and have the same bore and stroke...but there is alot more aftermarket parts for the '88 and up, thats why I was going to change it out. I guess what I'm really wanting to know is which one is better. The '87 for some reason just looks visually better, but I'm sure Suzuki had a reason for changing the design, most likely to make it faster, thats what I'm trying to figure out.

BTW, I know the cranks are a little different between the '87 and '88 but remember that thread I had just about that? I think it was OldSchoolin that called Wiseco for me and asked them and they said the '88 crank would fit in the '87. I guess it was a different and hopefully better crank design.

[Wickedfinger]

The '87 for some reason just looks visually better
What would that have to do with anything?.

Anyway, I think what you really want to know is, is the stroke the same - the bolt pattern on the Jugs look identical. Personally, I would stop wondering about this jug nonsense and just take your whole '87 motor to a good shop and have them do some head work, blueprint, and port it for you. You would see far greater gains just by doing that and never have to worry about this somewhat goofy scheme of grafting the later jugs to the '87 bottom end. In any event, I've only ever owned an '85 and the '90 so my help, and you don't seem to want to call it that based on the tone of your response, ends here. If you must insist on continuing on this quest, you probably want to ask Guido from http://www.quadracer.com/ . If anybody can answer your questions, he can. I'm pretty sure he is a regular on ATV connection's chat rooms. In any event - good luck.

[hondaATCman]

so my help, and you don't seem to want to call it that based on the tone of your response, ends here

Woa, I didn't know I sounded rude or anything... I just started typing and hit "submit" I'm sure if I proof-read I would have changed my words around, I was just trying to re-word my poorly written first post. Sorry if you took it the wrong way.


Personally, I would stop wondering about this jug nonsense and just take your whole '87 motor to a good shop and have them do some head work, blueprint, and port it for you. You would see far greater gains just by doing that and never have to worry about this somewhat goofy scheme of grafting the later jugs to the '87 bottom end.

I'm not saying that an '88 cylinder would beat a modded '87. I want to make the swap because there are a few more aftermarket parts for the '88 and up, than there is for the '87. For example a Wiseco Pro-lite piston, Boysen rad valve, Boysen Pro Series reeds, and L.A. Sleeve cylinder sleeves. The stock bore and stroke are the same and the '88 cylinder does bolt on the '87 cases, I did some research and test-fitted the cylinder before I even thought about making this thread. When I put the motor back together, I am going to send it off to have the whole works done to it.


The '87 for some reason just looks visually better

Oh, I meant that the sleeve and the port design somehow looked visually better, not like the shape or color of the jug. Sorry for the confusion.

By the way, thanks for the link!!

[370banshee]

the 88-92 cyls are a better design to port. but the 878 shince in the fact of air fuel delivery. it;s BIG!!! anyway the bore and stroke between teh 87 and the 88-92 are just a tad different. if you get a 88-92 crank then i;d say use that same style cylinder. btu if you keep the 87 crank stayt qwith the 87 cyl. i have a 87 lt250R and i'm kepping the 87 stuff on it. if you look a bit harder you'll see that most things made for the 88-up are also made for the 87. if you want reeds check out the G3 reeds by 1dr racing. they make a nice reed cage for the 87

[OldSchoolin86]

anyway the bore and stroke between teh 87 and the 88-92 are just a tad different.

The 87-92's bores and strokes are the same. The pistons are different in the 87 most likely due to a change in the pin(crank difference maybe or deck hight change). The only bore and stroke differences are between the 85/86 at a 70mm bore / 64.8 stroke and the 87-92 at a 67mm bore / 70mm stroke.

[370banshee]

i knew they used a differnt crank and piston and cyl. that why i figured they were just a tad differnt but i guess that pin hieght would wannt those new parts also except for the cyl. i guess.