450 Super Singles

[FlangMasterJ]

These things look like fun.

JH3Sdmit29Q

[Edbear]

I reckon they're going to really take off! These look like about the most fun you can have next to a motard!

Hope they do get them going and they attract attention in NZ! I think even I could ride one of those on track!

[motorbyclist]

where's the yamaha?! (http://www.kiwibiker.co.nz/forums/showpost.php?p=1468346&postcount=31)

(see other thread here) (http://www.kiwibiker.co.nz/forums/showthread.php?t=68722)

[madbikeboy]

I'm trying to build a variation on the idea now - I've got a Honda RS125 that I'm pulling the motor/box out of, and I'm looking for a CRF450 to stick in it.

Anyone got a 450 motor, or wanna buy my 125 motor (and heaps of spares including 2 cranks)?

MBB

[motorbyclist]

just out of interest, why the CRF? any reason you wouldn't take a YZF or anything KTM?

please, please consider using a CR500

[pete376403]

just out of interest, why the CRF? any reason you wouldn't take ... anything KTM?

It's already had a motor that needs rebuilding every 500km...:rolleyes:

[Coyote]

just out of interest, why the CRF? any reason you wouldn't take a YZF or anything KTM?

please, please consider using a CR500
Nicer looking twin spar frames rather than old tubular style I'm guessing. Yamaha have just come out with alloy frames but they're still similar to the old shape.


Stupid Xtra Broadband. Going to be waiting here forever. Not sure what you're on about yet but I'm sure I've thought of making my own one.

[speights_bud]

I rode a 'NSR600' at Manfield once. It was a NSR250 frame with a XR600 shoehorned into it. And Hell yea the bike was A LOT of fun, it'd be great on the infield at Taupo! Really lightweight, HEAPS of low down torque, had fun playing around, compression sliding and powersliding that day :) Lacked a bit in the top end though, as you'd expect with any large capacity single.

[motorbyclist]

It's already had a motor that needs rebuilding every 500km...:rolleyes:

+1

i didn't want to just say yamaha as per usual, and i thought i might be willing to put up with a KTM.

just my experience with thrashing the YZF400 and 426 engine is they're indestructible:)


Nicer looking twin spar frames rather than old tubular style I'm guessing. Yamaha have just come out with alloy frames but they're still similar to the old shape.


the guy already had a road frame and was fitting the motor from a dirtbike.

and i dunno about you, "nice looking" is not an important feature when i'm looking at chassis. strength, weight, and handling are a wee bit more important;)

as per my first post in here, they do do the yammy with the old style frame also.

[Coyote]

the guy already had a road frame and was fitting the motor from a dirtbike.

and i dunno about you, "nice looking" is not an important feature when i'm looking at chassis. strength, weight, and handling are a wee bit more important;)

as per my first post in here, they do do the yammy with the old style frame also.
Just got to see the video. Now I see they were using road bike chassis. I was thinking of bikes like the modded Aprilia SXV550 that was on KB a while back that was a motard with RSV forks and shock and with road bike fairings.

These bikes look awesome. Only problem is there is hardly any motors around and the best way is to buy a dirt bike and swap the motors around. You get a super single and a very quick (top speed) dirt bike :D

[Edbear]

Just got to see the video. Now I see they were using road bike chassis. I was thinking of bikes like the modded Aprilia SXV550 that was on KB a while back that was a motard with RSV forks and shock and with road bike fairings.

These bikes look awesome. Only problem is there is hardly any motors around and the best way is to buy a dirt bike and swap the motors around. You get a super single and a very quick (top speed) dirt bike :D

Now an SXV550 motor in an RS250 chassis...:2thumbsup

[HenryDorsetCase]

Just got to see the video. Now I see they were using road bike chassis. I was thinking of bikes like the modded Aprilia SXV550 that was on KB a while back that was a motard with RSV forks and shock and with road bike fairings.

These bikes look awesome. Only problem is there is hardly any motors around and the best way is to buy a dirt bike and swap the motors around. You get a super single and a very quick (top speed) dirt bike :D

in all the 450 single stuff I have seen in magazines or on the net the idea is that you use your MX bike frame, motor and swingarm. Strap on another front end and a shorter shock, staple on some bodywork (RS125 comes to mind) and go racing.

I want one:

a) because I like singles ; and

b) I think it would be a blast; and

c) don't they just sound fantastic?

[HenryDorsetCase]

Now an SXV550 motor in an RS250 chassis...:2thumbsup

been done, there's links on here.

[Edbear]

been done, there's links on here.

Looky wot I found!

http://sameerkumar.blogspot.com/2007/06/david-howard-aprilia-rs250-sxv-550-rsv.html

[madbikeboy]

So, my logic:

I had a couple of directions one was to buy a CRF450 (or KTM or whatever), and then find forks, wheels, fairings etc. I figured that even if I got the CRf for free, I'd still be spending moonbeams...

So, I've been eyeing up RS125's and RS250's for a while. Great handling bike, the frames on the 250 are stronger, and if you figure an aimed 96kg, then the 250 becomes a bit lardy when you figure a large single. Plus, as singles get larger, you run into piston speed issues etc.

So, the RS125 starting looking like the go. They're really small, but they're superlight to start with, very good handling, have good wide fairings, and good space between the spars of the frame. Single disc front wheel. It then becomes a engine swap exercise... And from the measurements that I've done so far with my eyeball micrometer, I think the Honda CRF450 motor should swap in without too much swearing.

The bike won't have huge power, but it'll have a very good power to weight ratio. Plus I can run it about 4 different classes.

Or, and this is the worst case, which isn't all that bad - I can continue to run the 125 stroker (I like little stinkpots) and I've got enough spares for at least a couple of seasons...

I've got the RS125 motor and parts on trademe - loads of interest and a tonne of watchers... Now all I need is a buyer and a donor motor from a motocross bike (and if anyone has got one, I'd be really keen to hear from you!).

BTW, this was inspired from reading Performance Bikes and reading F5 Dave's diary... I don't even care that much about the racing, I just want to build something cool.

[Coyote]

in all the 450 single stuff I have seen in magazines or on the net the idea is that you use your MX bike frame, motor and swingarm. Strap on another front end and a shorter shock, staple on some bodywork (RS125 comes to mind) and go racing.

I want one:

a) because I like singles ; and

b) I think it would be a blast; and

c) don't they just sound fantastic?
Awesome cause that's the way I'd do it due to cost. Thinking of doing it to an XR650. Preferably in a way that could be reverted back to a Motard or Dirtbike. Looks like the bikes in the video have road bike chassis though. Not sure what the Kawasaki is but the Suzuki looks like an RGV and the Honda looks like an RS250

[Atlas]

A big single in a lightweight chassis would make a great road special, a modern take on the cafe racer concept of tritons and tribsa's.
But for racing, big singles are already catered for by super motard or for that matter classics.
Why stop at a 450 when 600+cc gives more stomp.
The sound of a big single with an open pipe, nice...

[Mental Trousers]

Lyndon from Boyd Motorcycles in Hamilton runs a CRF450 converted to a super single in Formula 3. Don't know if he's done anything to the motor but you can see the thing pull a good 10m gap on anyone coming out of a corner. Sticks like dog shit. It was quick enough for him to pull 3rd/4th's all day long at club level.

[motorbyclist]

Just got to see the video. Now I see they were using road bike chassis. I was thinking of bikes like the modded Aprilia SXV550 that was on KB a while back that was a motard with RSV forks and shock and with road bike fairings.

These bikes look awesome. Only problem is there is hardly any motors around and the best way is to buy a dirt bike and swap the motors around. You get a super single and a very quick (top speed) dirt bike :D


A big single in a lightweight chassis would make a great road special, a modern take on the cafe racer concept of tritons and tribsa's.
But for racing, big singles are already catered for by super motard or for that matter classics.
Why stop at a 450 when 600+cc gives more stomp.
The sound of a big single with an open pipe, nice...

GAH!


the idea is that you can buy a stock dirtbike brand new for $13k, slap on a front end from a sportbike, lower the rear a bit to match, get a set of rims and then slap on some fairings. all up a brand new racebike for under 20K, and the bikes both already conform to engine/emission standards from the MX comps and will create a fun new class for people to race in without having to buy a dodgy bike from the early 90's from an overpriced road market

[Coyote]

the idea is that you can buy a stock dirtbike brand new for $13k, slap on a front end from a sportbike, lower the rear a bit to match, get a set of rims and then slap on some fairings. all up a brand new racebike for under 20K, and the bikes both already conform to engine/emission standards from the MX comps and will create a fun new class for people to race in without having to buy a dodgy bike from the early 90's from an overpriced road market
Well sweet then, that's way better than I thought. Could've sworn by the looks of them they were like road bikes, especially the Suzuki.

Reckon an XR650 would be good for it then? Something I don't have to rebuild so often. Plus I've got a VFR400 swingarm that could go on it so I'd have a nice 150 section tyre on the rear. Unless that's too fat.

Here's the Aprilia I mentioned: http://aprilianews.blogspot.com/2007/09/aprilia-of-week-rsx550.html

[motorbyclist]

damn that looks nice!:drool: