185s vs 200s top end rebuild

[etdust]

I have a 1983 Honda 185s.

Question.  It appears time to rebuild the top end and i was wondering if I can use one of 200s rebuild kits and put that cylinder jug on it or if it will fit?  So basically i am wanting to use the 200 cylinder and the 185 bottom end and heads.  I think it'll work, but hence the expertise this site has figured I'd ask around.

 

[Grease Monkey]

@Mac used to work on the Hondas. Maybe he knows. 

 

[Mac]

Never worked on the 2 smokes.

I don't think you'll gain much with just 15cc.  Personally,  I'd stick with stock.

 

[Brian Machnach]

back in the day bunch of use in are late teens bought little xr50 and pw50 to rip around in the streets.my buddy blew up his Yamaha pw50 and ordered a Yamaha tri zinger 60 jug kit and head.then his dad took the head  on a big sheet of a fine grit  sand paper on a flat surface and rubbed it in a figure 8 a bunch of times and shaved it down.it all bolted up and seemed to work.the little sucker turned out to be the fastest one in our group.just some old school backyard hack trick that seemed to work.

 

[Rorschach]

When I was a kid we played around with a lot of those little Honda 185s and 200s. We were very young and the furthest thing from an experts. If it visually looked like it would fit we'd put it together. But I do remember swapping a lot of top end parts around between the two and not having any issues. Hell we would forget which was which and couldn't tell you what engine was in our trike without looking at the casting where it says the CCs. I do remember getting the cam timing off on a buddy's 200s one time. We had the cam timing delayed by one tooth thus retarding the valve timing quite a bit. Had to pull it with another bike to get it started but it had crazy power. Was blowing away 350Xs and 250Rs. Shook like an old Harley and ran hot. Realizing our mistake we purposely did the same thing to an XR200 with the same result. Just an insane amount of power coming out of that little 200. Stupid kids! I'm pretty sure the only difference between your 185 and a 200 is the diameter of the bore though. So as long as you use a 200 piston with a 200 jug it should work. 

 

[xtracrispy]

Pretty sure I remember reading most of the 185 and 200 parts interchange. Including the 83-85 200X and 2 valve xr/xl 200 (with exception of whatever years they had dual carbs)

so I think you’re good to go

 

[etdust]

Ok.  Thanks for the replies.  I am going to give it a shot and we will see how it goes! Thanks for the input.

 

[Stinky]

What is the dif in bore?

Does anybody make a big piston?

ImHO...no replacement for displacement, and an almost 10% gain is worth investigating