Two Stroke Maintenance

[Liono]

I'm currently in the process of deciding what 125 bike to go for. I quite like the idea of a two stroke, especially the NSR, and I get the impression through a search on the board that two strokes require more maintenance than four strokes.

Now, although it is difficult to quantify, could anyone give me an idea as to how much work will be involved in running an NSR (probably an older one, I will be able to spend up to a grand on it). Is it probable that it will be off the road for 1 day in every 7 and will I have to spend hours each evening fiddling with it?

Any advice or useful links would be much appreciated.

[stinkwheel]

Depends a lot on the state of tune, in standard tune the NSR is pretty robust and they are simple (but precisley engineered) engines. Honda build quality usually wins through.

Tuned bikes get progressivley less reliable the more you tune them (that applies to all bikes). Because they rev more quickly and use oil in the fuel rather than in the sump for lubrication of the engine, 2-stroke engines wear out more quickly. I normally expect to get 20,000miles out of a 2-stroke engine before it needs a rebore and new piston rings. Routine maintainance is simpler on a 2-stroke and a top-end rebuild (rebore and rings) isn't all that major a job but challenging enough for a beginner.

As a general rule, the less you fiddle, the less you need to fiddle.

Remember that if you are buying a second hand NSR that it may have been owned by someone on here and had the arse ragged out of it every day of the week for the last three years . It may also have been maintained by a 17 year old who is not all that expert at doing the jobs (look at some of the questions in the workshop section). Take someone with you who knows what they are looking at to avoid buying a pig in a poke. There are a lot of bad-uns out there, especially at the cheaper end of the market, I would probably look for an older model in totally standard trim with low mileage rather than a newer one with a lot of miles on it.

Others may disagree.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Liono]

Thanks for that Stinkywheely, you've given me some really useful information, I like the sound of:

[Kickstart]

Hi

In some ways a 2 stroke does need more maintenance. The NSR has a plated bore so cannot be rebored, but then it should also not reall wear out (although you might well still need to replace the pistons and rings).

4 strokes generally need the oil changing more often and have lots of nasty valves to adjust.

Also, if you managed to get a 4 stroke 125 to produce the same amount of power as a full power NSR (~24hp at the back wheel) then it would have the life expectancy of a hand grenade.

All the best

Keith
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