Hi guys...

I am a 2 stroke bike nut. Mainly Kawasaki Triples. My main rider is an H2 750 cafe bike that has been modified with a bunch of go-fast/stop-fast/go-around-corners-fast parts..all keeping in the spirit of a vintage cafe racer. I love this bike and it always puts a smile on my face.



I've been secretly in the market for an NSR for 4 or 5 years now. As far as modern bikes are concerned, they are basically #1 on my list of "must haves". Unfortunately, where I live they just do not exist (Minnesota). And ebay prices with shipping always put them out of my price range.

Long story short, and after some agressive "shuffling" of funds, I now am the happy new owner of a '91 MC21.



Let me start by saying that although I know my way around a 2 stroke pretty well.... I know NOTHING about these bikes and I am anxious to learn. As you can imagine, I am on an absolute Island when it comes to support in my area as I have never seen another on the road.
Although the bike runs, and seems to run well. It has been sitting for 2-3 years and I would like to know what you guys recommend in terms of maintenance and things I should look for.
I also would like to purchase a Service Manual as the one that came with the bike is in Japanese. Any help in finding one would be greatly appreciated... English prefered please..

I look forward to all of your replies and I cant wait to get this thing on the road!!!!

cody

Hi Cody, and welcome.

That MC21 looks familiar. I'm sure it's been owned by someone on this Forum before. If it had mild steel pipes I would've sworn it was an MC21 I supplied to a guy in Minnesota back in 2000!

You should find most of what you need on the Main Site and in the Forum, so have a search around and then come and ask anything you are unsure of.

Cheers,
_________________
Andy.
NSR-WORLD.COM

Please keep all responses to Forum posts on the Forum so that others may benefit.

Please DO NOT PM me for technical advice. My time is precious, and you will probably receive a faster response on the Forum anyway.

Check us out on Facebook! Please "like" our page!

scrambler73 wrote:Hi guys...


I've been secretly in the market for an NSR for 4 or 5 years now. As far as modern bikes are concerned, they are basically #1 on my list of "must haves". Unfortunately, where I live they just do not exist (Minnesota). And ebay prices with shipping always put them out of my price range.

Long story short, and after some agressive "shuffling" of funds, I now am the happy new owner of a '91 MC21.


Let me start by saying that although I know my way around a 2 stroke pretty well.... I know NOTHING about these bikes and I am anxious to learn. As you can imagine, I am on an absolute Island when it comes to support in my area as I have never seen another on the road.
Although the bike runs, and seems to run well. It has been sitting for 2-3 years and I would like to know what you guys recommend in terms of maintenance and things I should look for.
I also would like to purchase a Service Manual as the one that came with the bike is in Japanese. Any help in finding one would be greatly appreciated... English prefered please..

I look forward to all of your replies and I cant wait to get this thing on the road!!!!

cody

Interesting H2, But I think you'll like the handling of the NSR better, but lacking power compaired to the H2. Where did you find that NSR and how much did it set you back? Is it street registered? Your not going to find any manual in any language except Japanese. The web site and Jamie's web site are the best resources for parts and technical information. You can order just about any part you need from www.redline-ci.com. Tyga is also popular, but shipping costs are expensive.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

Forgot to mention: as you should know, if the bike has sat a while the seals may have dried up which can induce an air leak and seizure of the motor. My bike sat a couple years before I bought it and I need a new crankshaft, which technically are not rebuildable on Hondas.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

thanks for the replies!

Wow! No service manual in english? I will definately be visiting this site and filling my head with NSR knowledge. Are torque specs, wear limit specs, etc found here?

The bike was started regularly, but was rarely ridden. and yes, I am very well aware of crank seals drying out. All of the triples that I have purchased get a crank rebuild as a starting point. (would you trust 30 year old rubber?)
as far as the Honda crank, Does the NSR use an aluminum labyrinth seal?, or are all the seals rubber?

Andy, I believe the bike came from Florida in 2003-ish? and yes it has a free and clear title and is street legal. I cant imagine there are many around like this that look similar? It would be great to find another guy in Minnesota to bounce things off of!

As far as reliability, what seems to be the main problem issues with these bikes? What to look/listen for??
With the triples, especially the H1/H2, it is the poor quality of the metal used in their transmissions. In stock form (50-70 HP), they hold up ok, but when you start to surpass the 100RWHP mark, they dont hold up...other than that, once you get them sorted, they are amazingly reliable for an aircooled 2 stroke.

thanks again, cody

scrambler73 wrote:

Wow! No service manual in english? I will definately be visiting this site and filling my head with NSR knowledge. Are torque specs, wear limit specs, etc found here?


Does the NSR use an aluminum labyrinth seal?, or are all the seals rubber?

I cant imagine there are many around like this that look similar? It would be great to find another guy in Minnesota to bounce things off of!

As far as reliability, what seems to be the main problem issues with these bikes? What to look/listen for??
With the triples, especially the H1/H2, it is the poor quality of the metal thanks again, cody

Wear limits aren't so much an issue. Its more likke: when it breaks its time to replace it. The cylinders are nikasil which is pretty hard to wear out.

Crank seals are all rubber.

The paint job is a replica of an MC28SP limited edition. Not too many around.

Reliability? Mostly electricle problems these days. The NSR relies on a computer to control advance and power valves, as well as a host of other things. ...and its all getting old. Problems are rair though.

If your H2 is only making 50-70 hp, you should find the NSR a little quicker. With simple mods, which should have allready been done to your bike, you should see see 60hp easy.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

Congrats ! now someone has a nsr closer to me

This is what we like, new peeps and pictures of new bikes, excellent!
_________________
Please do not PM me technical questions, if you can't find it on the Forum start a thread

thanks J.

I'll wait for something to break then... She seems to pull hard and my butt dyno says 60 HP. Supposedly it dynoed at 62 at the wheel?

Its funny you say "parts are getting old".. To me 15 years old is brand spankin new!!! All of the electronics (CDI's Stators Etc) I am used to are 30+ years old!!!

As far as availability, are most parts still available through Honda? Or has it become a monopoly for the guys that were smart enough to buy it up when it was still available???



and just an fyi.....a STOCK H2 puts out about 60-70rwhp, mine is "slightly" modified. Its somewhere in the neighborhood of 90 now and is 100 pounds lighter than stock. I know of a street H2 with an honest to goodness 145 rear wheel..It has a tendancy to powerwheelie/spin the wheel at 80 mph. The thing is nuts.
And there are a few drag guys squeezing waaayyy over 200 hp out of the old H2 engine. Last year one went 7.77 at 170mph and broke (destroyed) the old record for 750cc.

and RVT, I know of a few guys in Illinois and Michigan that have some wicked 2 strokes (Gamma's, NSR's, RGV's Aprilia's). You probably know of some of them.
Still have yet to meet anybody in Minneapolis though that actually rides their bike. I know of a couple of Gamma's and RZ's, but they just sit and sit and sit.

I like to ride.

What I meant by getting old is that the parts have reached the end of thier service life, especialy electric things. Pretty much everything is still available though. The MC28s were made till '99 and most all the parts are interchangable. Some things you may have to wailt for. My new crank won't be here till mid august now, and I have had a couple pices of body work on backorder for a couple months. I did get my new Rothmans tank today though.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

Are the cranks pressed together? If so, I dont see any reason why new seals/bearings couldn't be pressed on? Im sure someone out there has sourced rods, seals, etc and has done it.

I think Kawasaki also sold there triple cranks as "non-rebuildable" and so far I've had about 7 or 8 of them done..

It would be nice to save a few hundred $$ whenever possible.

once again thanks for the welcome and info. I have a feeling I will be bugging you guys for years to come

The cranks are pressed together, but the pins are made onto one side. So if you have a bad pin, you need a crank. Also, Honda does not sell any replacement parts. It is possible to get bearings though outside sources, but not the rods or ears. Yes everything can be fixed if you want to spend the money. In my case the cost was close to a new crank so I just decided to spend a little extra money to make sure it was right. The bearing alone were $300, $50 each for used rods, and $300 labor, and this was assumuming I didn't have a bad pin, which I'm sure I do. New crank is $750 (was $650 when I ordered it).
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

scrambler73 wrote:thanks J.

I'll wait for something to break then... She seems to pull hard and my butt dyno says 60 HP. Supposedly it dynoed at 62 at the wheel?

Its funny you say "parts are getting old".. To me 15 years old is
and RVT, I know of a few guys in Illinois and Michigan that have some wicked 2 strokes (Gamma's, NSR's, RGV's Aprilia's). You probably know of some of them.
Still have yet to meet anybody in Minneapolis though that actually rides their bike. I know of a couple of Gamma's and RZ's, but they just sit and sit and sit.

I like to ride.

I know someone thats close to you i think he lives in S. dakota. Hr got vj23, rs250 and some 4 stroke grey market bikes