So my first post on here after lurking for a fair while, thought I'd post up my progress with the build so far. The bike is an 87' MC16 that had been owned by a group of friends since it was imported, it was taken off the road after a gearbox issue arose and ended up stood at the back of a garage for 15 years.

The guy I bought it from decided to start stripping it down to restore, he had a lot of work on his hands:


I saw the bike listed on a certain auction site and thought it would have a bid and see how my luck turned out. I have never even ridden a 2 stroke before so I knew I had to have one someday, I have always been a fan of the NSR's so I was glad I got this gem for a sensible amount of money.

The guy selling it had given up after fixing the gearbox problem (worn selector fork) and had the bike stripped right down to the bare frame and wheels. I actually bought the bike back in April but it has been sat pretty much untouched due to me being busy with my NC30 and CBR600, but now the rebuild begins in earnest.

Engine on the bench ready for top end inspection:


The engine turns over very easily with no tight spots but I thought it was worth checking the top end:





The RC valves needed a good clean:








However it looks like I have small cracks in both exhaust ports struggled to get any photos but I think a re-plate or some new barrels are needed, it's tempting to use them as they are the bike was probably being run with cracked bridges for god knows how long but it would nag at me every time I use the bike...

I've also put the subframe, loom, airbox etc re fitted. She is small even next to my NC30 which is no barge itself!




Clocks where cleaned up and installed:


And this is where I am now, still a long way to go:


Hope you all like the progress so far, I will keep updating as things progress.

Kieran.

Hi Keiran
Good to see an earlier NSR given a new lease of life it looks like it will make a nice little when finished,
Good luck with the build,
jonnymac
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John

Hi Kieran sorry for spelling your name wrong,
Jonmac
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John

Don't worry everyone spells my name wrong :p hopefully it will be a nice bike when it's done, all the bodywork is original and in good order, but it won't be getting a full restoration, just a tidy up to make sure it's a good runner. I want to keep it standard looking but I may try and squeeze a few more ponies out of the motor, anyone got some mc18 barrels for sale?

Thanks Kieran..............I love re-build/re-furbish threads..............Keep up the good work.

So its been a bit of a wait for some parts to come through but got the last bits I need for the engine so went down my unit today in the pouring rain to get a bit of work done.



Decided to go for the mitaka pistons in the end as I have heard a few good stories about them, they look good quality and the ring pegs are in exactly the same positions as oem which was my main worry.

Had to spend nearly an hour scraping the old gasket off the cylinder:


Little end bearings looked and felt fine but thought it would be best to replace:



Not really much of a difference between old and new considering one is getting on for 30 years old, new ones installed with plenty of 2 stroke oil:



Rings installed on the new pistons and fitted to the rods:






New RC valve oil seals and e rings fitted:


Cylinder re fitted with new base gaskets, I was quite paranoid that the rings had slipped off the rings pegs so I took the barrel off once or twice to check before finally tightening it all up:


Thats all I managed to get done today, hopefully will get back down there tomorrow to do the top cylinder and make a start on getting the engine back in the bike. I know most will be wincing at the use of non OEM Pistons but if they are good enough for all the KR-1 owners to use with their fragile engines im praying they will be fine for me and the hopefully more robust NSR unit.

nothing wrong with mitaka pistons mate
and well done on your first 2 stroke ,i would have done the crank seals while i was in there as it was stood for 15 years !
it will cost you big if it goes ,my mates has gone twice now once on his old engine then one that had been so called stored correctly .
you will love it when you get out on it
but id get a set of seals and do it right especially while the motor is out ,dont even know if you can get crank seals for them as ive not had an mc16
see what others say about it ?

Hi mate thanks for the reply, do you mean getting the crank split to do the centre seal or the outer two? Is it a difficult job as I have rebuilt 4 stroke heads before but never split cases to do bottom end work?

I did do a bit of reading up and mc16 seals are NLA but later ones will fit but will be recessed rather than sit flush, looks like the engine build might be delayed a little longer as I have the seed of doubt in my head again lol, I'm guessing failed crank seals let air into the cases and cause it to run lean and sieze up?

Nice work Kieran. It will be interesting to see how those Mitaka pistons go, as you say plenty of other people use them so cant see why they shouldnt be okay.

If you are worried about your crank seals you need to carry out a leak down test, this will confirm whether or not they are leaking. If you do a search there is a recent threard on here about how to make a kit and carry out the test.

Stripping the bottom end is a very straight forward job on these bikes, if you have managed to take your engine out and strip and rebuild the top ends it shouldnt be a problem for you.

If the centre seal has gone then you are looking at a crank rebuild which isnt as big a problem as it used to be, genuine main bearings are available still if you know the right people and I recently bought a new mc16 centre seal from another forum member who bought a batch from Japan. It was his last one but hopefully he should be able to point you in the right direction if it turns out you need one.

Hi Paul, yea im no engineer but the pistons and rings look very well made, hopefully I wont have any issues as long as I run it in properly.

Ive had a bit of a search and I will probably go for the old school route of filling the crank cases up to see if any leaks past the seals, when I first stripped the heads and had a look into the crankcase it looked as if someone had filled it with 2 stroke oil or similar previously so heres to hoping it will be ok.

I want to avoid splitting the cases just yet as when I do the crank will be getting a full rebuild which id like to save for another day due to the cost etc.

Well ive made a little bit of progress but its been slow due to the poor weather putting me off sitting in a cold metal container working on the bikes, got the engine finished and back in the bike, also fitted the carbs and airbox today, lots of fun with nice hard airbox rubbers that refused to fit on the carbs but we got there in the end.



Next job is to get the chambers blasted and painted. Being a newbie when it comes to strokers is it worth getting them de coked before I go any further? And is this something that can be done at home or best to get them sent off somewhere?

Kieran.

https://www.youtube.com/watch?v=R0RCUe7exvI

Not recommended but amusing

Haha Looks like its done the job, so realistically on a bike that's done 34000km is it worth doing them or should they be fine as is at that sort of mileage?

Hi Kieran

Where did you purchase your little end bearings?
I am going to do a top end refresh in a few weeks with Mitaka pistons and rings but totally forgot about little ends.
Your project looking good,
Cheers

Daz
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stink wheels forever.

Bought them from David silver spares if I'm not mistaken, I've used them a lot in the past and never had a problem, bit of a wait if they don't have them in stock though.