Hi everyone,

Thanks to everyone who answered my last post. I have a new question

Im just curious to how long do rings, pistons, barrels, bottom end usually last on an engine used on the street? Will I have to replace just the rings at a certain time or the complete top end?

Thanks again!

On my bike it was about 5 minutes LOL

Seriously a 2 stroke is only as reliable as the owner services it, Most suffer from neglect but these days its people like us who pick em up and sort them out!...

The Honda like others, need top end around 10,000km's and Bottom checked / redone at 20,000km's As for Barrles, they shouldnt need done unless they get damaged or wear excessively, Rings with every top end but no harm in replacing them after 5,000km's

There will be some more tech guys along soon but thats a rough outline... Also check Andy's site the workshop, Tunning section all has usful info well worth sitting down with a coffe and having a read over...

Cranks last a long time, 30,000k's is the "service interval", plenty go past that without trouble and the age of the middle seal (it's replacable on the MC21 and 28 but not on the '16 or 18 ) seems to give more problems than the bearings themselves. Run it on good oil and be nice to it, don't for example coast downhill with the throttle closed. Dip the clutch a blip the throttle a bit, that's the only time it gets any oil, the rest of the time it's spinning dry.

Barrels don't wear they just get damaged, so in theory they just about last for ever, a decent 2nd hand original plating Honda barrel would be my choice over a fresh replated job every time, if it costs £100 on ebay and comes with a piston, rings and a little end all the better.

As for rings, well, for most of us it's every time it seizes or drops a horse or two on a dyno day, except for Steve who does his every other Monday.
But IF you manage to run it just as a road bike and leave it in completely standard form the service interval is 10,000k's, I believe Leigh's '28 roadbike is way way way past that as Leigh like most people is reluctant to rip down an engine that's running well.

But (in my opinion) it's also very important who does the work, I'd advise do it yourself, yes you'll make mistakes, yes it will cost you money (but not as much as a mechanic will charge) but it's all a learning process and in a couple of years time you won't even bat an eyelid when the engine needs to come out.
But if you choose to let someone else do it make sure they know these bikes inside out, too many tales of wrong crank bearings, bit's left in crank cases, wrong heads on barrels etc. are on this site (and we're the people who take an interest in our bikes) after all if someones going to learn how to rebuild an NSR with your NSR, it may as well be you.
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Please do not PM me technical questions, if you can't find it on the Forum start a thread

Thanks alot for the replies guys,

I am for sure going to be the one doing the work. Ive never worked on a 2 cylinder 2 stroke before, but I will take my time and refer to this site if I ever have any problems. For the riding that I will be doing, its a perfect bike. Im not planning on doing any long distances or anything, just a bike to put around town on.

The only problem is deciding on which one to get. I could get an MC18 right now, but after doing research and seeing that parts will be harder to get i want to opt for an MC21. I like the styling on the MC21 the best out of all of the nsr's. I just have to find someone that will import me one now !

Thanks again!

update your profile so we can see were you are and maybe someone here may already have one for sale!! best of luck!

Mazdadude,

could be of some intrest to you! 130126105147 ebay number?

Thanks rc46, thats actually the guy that ive been contacting for info on the bikes. From what I know he imports them, so I might be able to get excactly what I want! Hes only about 2 hours away, I told him I would contact him at the end of the summer.

Thanks!