CRM80 build?

[CHOPPA]

Im not in too much of a rush, im building a bucket engine out of a CRM80 which is the same as a NSR80.

Im not sure if I should rebuild the bottom end with new rod and bearings etc? I dont like spending money so if its going fine now and theres not too much play in the rod ill prob leave it but it is a very old engine 1990 so its prob due....

The mods im doing are a 'non racing' 100cc big bore kit, 28mm PWK carb, CR85 V Force reed block and a Gianelli Expansion Chamber. I guess ill have to modify the head to suit the new cylinder too

I should be ok to tune it, ill prob start with the same carb specs as a KX100 seen they run the same carb.

What im not sure about is if the standard CDI etc will be good enough and if its not I dont really know where to start.... Could I fit a CR80 CDI? Or does the map on the CDI have to be mapped for this exact bike?

Any help or ideas would be great thanks!

Oh my goal is atleast 200hp at the rear wheel.....

[White trash]

Cheating cunt.

[CHOPPA]

This is pretty much what id like to build oh and BTW is going in a 1988 CBR250R er GP Chassis

http://www.dreamgate.ne.jp/NSR/Gallery/g9_jhansr80.html

[gav]

The mods im doing are a 'non racing' 100cc big bore kit,

Non Racing? Tui moment, anyone?
How do you know its the same as a NSR80?

If you've got the complete CRM80 why not leave it in that chassis, add 17" wheels and treat it as a mini motard? Probably be faster than trying to drag that big arse CBR250 chassis around?

[CHOPPA]

The mods im doing are a 'non racing' 100cc big bore kit,

Non Racing? Tui moment, anyone?
How do you know its the same as a NSR80?

If you've got the complete CRM80 why not leave it in that chassis, add 17" wheels and treat it as a mini motard? Probably be faster than trying to drag that big arse CBR250 chassis around?

The kit is designed for some old POS half road dirt bike thing, doesnt say anything about racing on it so all good. Na dont want a motard bike, there is not much left of the CBR so shouldnt be that heavy plus im 6'2

[F5 Dave]

yeah why spend money rebuilding the crank when its going?

& thus was my philosophy on building bucket engines for a few years. . . .Largely spent picking up pieces.

Any 2 stroke sat around for ages will form minor rust & then when thrashed mercilessly will wear that rust patina along with any surface that the big end roller bearing ran in, - off, . . . then one day, probably 1st or 2nd race meet; gall a little & the rollers stop rolling making a low contact area plain bush. A task they are ill equipped to cope with. All within a few seconds.

If you're lucky they spit the rollers up the transfers & the piston misses dragging them half way out & creating a trench up the barrel.


New crank seals while you are at it. With a Rod kit it should be reliable from here in.

[CHOPPA]

yeah why spend money rebuilding the crank when its going?

& thus was my philosophy on building bucket engines for a few years. . . .Largely spent picking up pieces.

Any 2 stroke sat around for ages will form minor rust & then when thrashed mercilessly will wear that rust patina along with any surface that the big end roller bearing ran in, - off, . . . then one day, probably 1st or 2nd race meet; gall a little & the rollers stop rolling making a low contact area plain bush. A task they are ill equipped to cope with. All within a few seconds.

If you're lucky they spit the rollers up the transfers & the piston misses dragging them half way out & creating a trench up the barrel.


New crank seals while you are at it. With a Rod kit it should be reliable from here in.

Thats what I was after, cheers!

[White trash]

Thats what I was after, cheers!

By the time you're finished this thing, the young fella's gonna be big enough to ride it.

[Buckets4Me]

Other parts included with the kit are a complete bore up kit which increases displacement to 93cc. It also comes with a specially ported and polished cylinder head that works in conjunction with the entire Jha full power kit to maximize performance.




I like the specially ported and polished head
wonder if it comes with crome push rods



So just how fast are these little NSR mini bikes. How about an additional 12 to 15 horsepower at the rear wheel which brings total power to 24 to 27 horsepower and a 15.884 second zero to 400 meter sprint ( the Japanese equivalent of the quarter mile ) the speed at the end of the timing lights was 127.47 km/h and a top speed of 150 km/h !!




shucks and my 18-19 h/p air cooled bike could only manage 160 km/h
so it starts with about 12 h/p at the wheels and manages 27 if all goes well ( and you find the same dyno jha use)


well after all that HAVE FUN building this bike of yours and make sure you finish it and go racing
dont trust what these salesmen say ( cause everyone knows you polish the outside and add copper)

and keep posting pics of the bike as you go along

[CHOPPA]

Other parts included with the kit are a complete bore up kit which increases displacement to 93cc. It also comes with a specially ported and polished cylinder head that works in conjunction with the entire Jha full power kit to maximize performance.




I like the specially ported and polished head
wonder if it comes with crome push rods



So just how fast are these little NSR mini bikes. How about an additional 12 to 15 horsepower at the rear wheel which brings total power to 24 to 27 horsepower and a 15.884 second zero to 400 meter sprint ( the Japanese equivalent of the quarter mile ) the speed at the end of the timing lights was 127.47 km/h and a top speed of 150 km/h !!




shucks and my 18-19 h/p air cooled bike could only manage 160 km/h
so it starts with about 12 h/p at the wheels and manages 27 if all goes well ( and you find the same dyno jha use)


well after all that HAVE FUN building this bike of yours and make sure you finish it and go racing
dont trust what these salesmen say ( cause everyone knows you polish the outside and add copper)

and keep posting pics of the bike as you go along

Thats not the kit im getting just some good info to send me in the right direction. Id be happy with about 15hp I guess

My proper racing gets pretty busy from December so it might not happen real quick but I am picking up the CBR tomorrow and the CRM next weekend

Only thing I have to decide on now is my colour scheme haha

[Kendog]

My proper racing gets pretty busy from December

You racing F5 as well?

[CHOPPA]

You racing F5 as well?

haha yeah something like that

[Buckets4Me]

Only thing I have to decide on now is my colour scheme haha

and where to put the number boards
and what number to use
NOT #9

and new tyres

so we should see you next weekend then

[Hilleye]

yeah why spend money rebuilding the crank when its going?

& thus was my philosophy on building bucket engines for a few years. . . .Largely spent picking up pieces.

Any 2 stroke sat around for ages will form minor rust & then when thrashed mercilessly will wear that rust patina along with any surface that the big end roller bearing ran in, - off, . . . then one day, probably 1st or 2nd race meet; gall a little & the rollers stop rolling making a low contact area plain bush. A task they are ill equipped to cope with. All within a few seconds.

If you're lucky they spit the rollers up the transfers & the piston misses dragging them half way out & creating a trench up the barrel.


New crank seals while you are at it. With a Rod kit it should be reliable from here in.

Seconded. Judging by my own experience recently, it'll last about one dyno session, two Friday testing sessions at Ruapuna then the main bearings will fail just before a major event like BoB.

[CHOPPA]

and where to put the number boards
and what number to use
NOT #9

and new tyres

so we should see you next weekend then

Got number boards sorted, new tyres sorted.

Not sure what number to run! Wow decisions decisions!

I think ill prob just put number 1 on....