NS 250r

[dlunn]

Has anyone ever seen a NS250R street bike? There is one for sale locally here. 90 degree twin cylinder 2 stroke race bike, 6 speed trans. I have seen some builds where people put a bike engine into quads but their usually big 4 strokes. I don't know if it would make a good atv motor but it would sure be a conversation starter everywhere you go.

[250Renvy]

Where, and how much?

If it's reasonable, I wouldn't mind getting a good look at one of those.

Based on what Troy has said about vibs, the 2 cylinder should cancel out some of the vibrations from a non-counterbalanced motor and would probably make a pretty fast machine although considering it's still a 250, I'm not sure it would be that much faster. The pipes would be the hardest part.

[dlunn]

http://toronto.en.craigslist.ca/tor/mcy/1935559647.html

Your only a few hours away. I thought the price looked good if you could sell the rest of the bike as parts.

I think having a 2 stroke street bike would be fun as well.

[jcs003]

Originally posted by dlunn
Has anyone ever seen a NS250R street bike? There is one for sale locally here. 90 degree twin cylinder 2 stroke race bike, 6 speed trans. I have seen some builds where people put a bike engine into quads but their usually big 4 strokes. I don't know if it would make a good atv motor but it would sure be a conversation starter everywhere you go.

the banshee got its powerplant from the yamaha rz350 road race/street bike. i dont see their being a problem with a twin 250 in a quad.

[troybilt]

Those are rare and would be a sick build up in a 250r, I wonder how heavy that motor is??... I think there is more of those bikes in Canada from what I heard. Don't let the custom pipes scare you off...

[250Renvy]

Price is a little out of my range for an experiment. I could probably swing 3K. I think I've seen them for $2500 range before but since they're rare, it's kinda what the price is when it's available.

50HP is pretty good, but you can build a 250R motor up to that so I'm not sure what would be cheaper.

Maybe an NSR500 is the way to go for monster power.

[mxduner]

I would bet you could pull big numbers out of that motor, just like you can on a banshee.

Years ago in the sled world, the big debate was about twin's vs. triple's. I read a good tech article about the difference's performance wise. The triples would always out do the twins in all out power because you had an extra cylinder to 'perfect' with porting and a pipe and overall tuning.

since then twin's have taken over, cause really a twin has more than enough snoose to get ya moving, but more importantly weight.
Reason i bring this up is, it is a little bit the same as the single vs. the ns250's 'set'
:D

[jcs003]

here is a pic:

[troybilt]

Originally posted by 250Renvy
Price is a little out of my range for an experiment. I could probably swing 3K. I think I've seen them for $2500 range before but since they're rare, it's kinda what the price is when it's available.

50HP is pretty good, but you can build a 250R motor up to that so I'm not sure what would be cheaper.

Maybe an NSR500 is the way to go for monster power.

I bet it would be one of those hp vs. torque discussions. I'd think a 300cc 50hp single would build more torque than a twin 125cc each cylinder @50hp motor... just do to the rotational inertia of the cylinders. That little 250r probably revs to the moon, that's how they are getting 50hp. I could be wrong though, I don't know much about those little motors. Either way would be a fun build, looking at the pic it would be a challenge to get the drive sprocket to work right being its about 6in in the "Y" direction too high compared to the stocker trx250r... its up there...

[IRISH-RACER-14]

they sell used 2 sell those at 125,250 and 85 cc

[mxduner]

Originally posted by troybilt
I bet it would be one of those hp vs. torque discussions. I'd think a 300cc 50hp single would build more torque than a twin 125cc each cylinder @50hp motor... just do to the rotational inertia of the cylinders. That little 250r probably revs to the moon, that's how they are getting 50hp. I could be wrong though, I don't know much about those little motors. Either way would be a fun build, looking at the pic it would be a challenge to get the drive sprocket to work right being its about 6in in the "Y" direction too high compared to the stocker trx250r... its up there... you are right on about the torque vs. h.p. and the sprocket thing too. my thought when i seen the pic.

either way. that thang is 1 beauty. what a piece of art

[jcs003]

Originally posted by troybilt
I bet it would be one of those hp vs. torque discussions. I'd think a 300cc 50hp single would build more torque than a twin 125cc each cylinder @50hp motor... just do to the rotational inertia of the cylinders. That little 250r probably revs to the moon, that's how they are getting 50hp. I could be wrong though, I don't know much about those little motors. Either way would be a fun build, looking at the pic it would be a challenge to get the drive sprocket to work right being its about 6in in the "Y" direction too high compared to the stocker trx250r... its up there...

i will have to disagree. v-twins are known for their torque output. thats harley-davidsons claim and kawasaki used it in their sales ad for the 650(v-twin) prarie.

the sprocket location is a definite obstacle.

[bigmatt61]

Isn't that bike, in essence, an old production version of a moto gp 250 class bike? Those things are silly fast on a track, but are crazy wound up to make serious HP.

I'd like to have it just as it is!

Matt

[SilverLake250R]

I found some torque specs...36.3 Nm which is ~26.8 ft-lbs @ 8500 RPM. The max hp is at 9500 RPM. Probably not the most quad-friendly engine, but it is sweet!

[troybilt]

Originally posted by jcs003
i will have to disagree. v-twins are known for their torque output. thats harley-davidsons claim and kawasaki used it in their sales ad for the 650(v-twin) prarie.

the sprocket location is a definite obstacle.

Maybe I should rephrase a little...

A 250cc V-twin rated at 50hp, probably makes less torque than a 50hp 300cc+ single... ...not V-twins in general, or multi cylinders for that mattter... however, on the other hand, I would bet a 250cc twin builds more rpm than a 300cc single at the same hp rating... just a hunch... or the bigger single builds torque at lower rpms than the twin... :muscle:

[jcs003]

Originally posted by troybilt
Maybe I should rephrase a little...

A 250cc V-twin rated at 50hp, probably makes less torque than a 50hp 300cc+ single... ...not V-twins in general, or multi cylinders for that mattter... however, on the other hand, I would bet a 250cc twin builds more rpm than a 300cc single at the same hp rating... just a hunch... :muscle:

it would be nice to see the comparison. espically in the 2-stroke realm.

[troybilt]

Originally posted by jcs003
it would be nice to see the comparison. espically in the 2-stroke realm.

yes no doubt... hp/torque curves would be nice to compare. I bet the twin could be built for low end if someone took the time. Also could increase flywheel weight too would help.

Regardless, I think it would be a cool build in a Pikes Peak type quad/race... or TT/Flat track... I wonder what that thing sounds like at 9500 rpm... probably like the old 250 GP bikes... which is baddddd...

[jcs003]

Originally posted by troybilt
yes no doubt... hp/torque curves would be nice to compare. I bet the twin could be built for low end if someone took the time. Also could increase flywheel weight too would help.

Regardless, I think it would be a cool build in a Pikes Peak type quad/race... or TT/Flat track... I wonder what that thing sounds like at 9500 rpm... probably like the old 250 GP bikes... which is baddddd...

yes, those old Gp 2-strokes sounded broke but they put up nice numbers.. kenny roberts on his bikes were crazy. that 750 2-stroke he rode. :devil:

[mxduner]

Originally posted by jcs003
yes, those old Gp 2-strokes sounded broke but they put up nice numbers.. kenny roberts on his bikes were crazy. that 750 2-stroke he rode. :devil: not the same brand but i bet sounds as good, but looks even better:devil:

[dlunn]

I've only just started looking at some of the older 2 stroke bikes and was surprised by what was available back in the day. From reading on other forums the people who love these bikes are very similar to many of us on this site who still love 2 strokes for their simplicity, ease of maintenance, and the overall fun of just hitting the throttle and hearing the sound. I found this website from Australia; these guys are all about 2 stroke bikes mainly the RS250 and the RZ350. The amount of aftermarket available is unreal. I look at this and I wonder if they have put all off this development time into this market why hasn't someone come forward with the same type of business model for the 250R. I don't know if they race the 2 stroke bikes anymore, maybe they do and that why the parts are still available, but it would be awesome if you could get the same for the 250R. I wish I had the money to start this type of business since I think there is allot of people out there that would love to own a new high performance 2 stroke quad.

http://www.twostrokeshop.com/TSS1100GP.htm

[red88r]

Originally posted by mxduner
not the same brand but i bet sounds as good, but looks even better:devil:

Nice....wouldn't mind that in my garage...oh and the bike too!!!!