Ninja 250 racer build thread

[bitaria]

The rear shock is in...
After drilling out top and bottom mounting holes to 12mm everything lined up and went in fine. There seems to be good suspension movement, no binding up etc., but I plan on doing a bit more testing with spacers.

First impression is that there is not enough static sag (using GSXR stock settings across the board).

[alex.s]

the engine and frame are a good 75 lbs lighter. you'll want to switch springs

[bitaria]

Originally Posted by alex.s

the engine and frame are a good 75 lbs lighter. you'll want to switch springs

GSXR spring rate is the same as stock Ninja, at least on paper. Fork is still stock, but will get professional re-valve at some point this winter.

[alex.s]

spring rate doesn't translate directly when you replace the reducer knuckle. i forget but i think the 05 gsxr is a 0.4 where as the ninja is 0.6. the triangle "knuckle" piece that the dogbones and shock mount to actually introduces a small sine-wave (because it rotates) into the compression graph to provide a more "progressive" shock compression. depending on how much the knuckle moves it can be almost nothing but it is there. the knuckle also acts as a reduction lever since the dogbones are mounted further out than the shock itself (or vice versa in many cases). the distances between the gsxr knuckle and the 250 knuckle are different.

[bitaria]

Originally Posted by alex.s

spring rate doesn't translate directly when you replace the reducer knuckle. i forget but i think the 05 gsxr is a 0.4 where as the ninja is 0.6. the triangle "knuckle" piece that the dogbones and shock mount to actually introduces a small sine-wave (because it rotates) into the compression graph to provide a more "progressive" shock compression. depending on how much the knuckle moves it can be almost nothing but it is there. the knuckle also acts as a reduction lever since the dogbones are mounted further out than the shock itself (or vice versa in many cases). the distances between the gsxr knuckle and the 250 knuckle are different.

Right, I mean the raw spring rate, linkage aside.

[Tough Noogies]

Originally Posted by bitaria

The rear shock is in...
After drilling out top and bottom mounting holes to 12mm everything lined up and went in fine. There seems to be good suspension movement, no binding up etc., but I plan on doing a bit more testing with spacers.

First impression is that there is not enough static sag (using GSXR stock settings across the board).

Random question:

Did you drill out the upper shock spacer / bearing to 12mm? Or drill out the GSXR upper shock hole to 12mm and then press in the Ninjette OEM spacer / bearing?

Curious because I will be doing the same soon and the language people use to convey what they did is always minimal. Haha

[bitaria]

Originally Posted by Tough Noogies

Random question:

Did you drill out the upper shock spacer / bearing to 12mm? Or drill out the GSXR upper shock hole to 12mm and then press in the Ninjette OEM spacer / bearing?

Curious because I will be doing the same soon and the language people use to convey what they did is always minimal. Haha

I drilled the gsxr fitting to 12mm. Didn't have to press it out or anything.

[sparkplug896]

talking about the rear shock.. what year make and model does gsxr have that fits the ninjas

[Tough Noogies]

Originally Posted by sparkplug896

talking about the rear shock.. what year make and model does gsxr have that fits the ninjas

Have a look through here the below thread link and the Ninja FAQ. Lots of suggestions on applicable years, etc. Hope that helps!

http://www.ninjette.org/forums/showthread.php?t=59486

[sparkplug896]

Originally Posted by Tough Noogies

Have a look through here the below thread link and the Ninja FAQ. Lots of suggestions on applicable years, etc. Hope that helps!

http://www.ninjette.org/forums/showthread.php?t=59486

thanks very helpful

[bitaria]

Made some progress!

Custom fairing stay mostly finished up, just need to add Vapor dash mount.

[bitaria]

With dash mounted



At this angle dash is hard to see, I will re-mount it leaned back more and do the final pretty welds. It's all spot welded for now.

[bitaria]

Final product!

[bitaria]

Eyes are in. Pinch bracket holds everything on 2 bolts, so easily removed for track and re-installed for street.




I wish I had a better welder... still lighter than stock fairing stay it would be better if made from aluminum, but my MIG can't handle it.

[Foxrider64]

Looks good.

Much lighter than stock for sure.

[bitaria]

Other than front turn signals electrical work is done. Bike can convert from street to track in a few minutes.



I'm still evaluating crash protection options, Shogun sliders kit seems like the best option, but price is rather high. Any suggestions?

[Foxrider64]

Originally Posted by bitaria

I'm still evaluating crash protection options, Shogun sliders kit seems like the best option, but price is rather high. Any suggestions?

In my experience- the little ninja's frame is too narrow for frame sliders to not inflict more damage than a crash.

They act as lever arms when the bike goes down and can twist the frame or break the engine mount.


I actually took the sliders off my bike when I converted it to track use.


Just my

[bitaria]

Originally Posted by Foxrider64

In my experience- the little ninja's frame is too narrow for frame sliders to not inflict more damage than a crash.

They act as lever arms when the bike goes down and can twist the frame or break the engine mount.


I actually took the sliders off my bike when I converted it to track use.


Just my

This is not the first time I hear this. I've seen some slider setups where they do not protrude from the bodywork, essentially race glass becomes disposable. With something like Shogun kit it would involve cutting down sliders to fit.

[bitaria]

Made a bit more progress. Pretty much gave up on eBay seller to send me the right linkage and made my own connector. Really just a threaded m6 rod with LH twist on one end and RH on the other, had to use a lathe to make it all work.

Now the bike is a runner but it will not rev well and dies at WOT, could need some fresh gas and I know for sure it is very lean, especially in cold weather. Carbs are next on the to do list.

[bitaria]

Contacting the Chinese rearset manufacturer to get the right parts has failed. They told me several times that replacement parts were shipped, but nothing ever showed up. Ended up turning a bolt to but RL and LH thread on it to make it work.

[bitaria]

In my last post I had a picture of a custom bolt I made to connect shift linkage. Today parts from China came as promised, it just took them a really long time to get here. They did send me 2 sets, so my spare kit is also covered.

That said the bike is not longer in my garage, it went to Dave Alexander of Fluid Suspension Science for you may have guessed - suspension work. He will also be ordering a few other bits like clipons, brake pads, and in general checking my work.

[shane liberty]

Hopefully you haven't cut the subframe on your bike yet. Just a heads up on that. Supersport/Superstock rules prohibits cutting or modifying the subframe. You'll get protested if someone wants to be a dick about it.

[bitaria]

Originally Posted by shane liberty

Hopefully you haven't cut the subframe on your bike yet. Just a heads up on that. Supersport/Superstock rules prohibits cutting or modifying the subframe. You'll get protested if someone wants to be a dick about it.

Nope, was not planning on doing anything.

[bitaria]

Got the carb off, but ran into a few questions around routing and what can be blocked off.

https://www.ninjette.org/forums/showthread.php?p=841372

I will be at the Ridge this weekend with 2-fast.org, 1st time out this year (and really in 3 years at a big track)

[bitaria]

Ready to go, just in time.

[chugs]

Originally Posted by bitaria

Ready to go, just in time.

Got any more pics of your clipon setup? Looks like yours are fairly low and had to cut your fairings to accomodate.

[bitaria]

Originally Posted by chugs

Got any more pics of your clipon setup? Looks like yours are fairly low and had to cut your fairings to accomodate.

Clipons are Vortex, and they sit below the upper triple, with controls rotated at a pretty steep angle down. I basically set it up the way I like and then cut fairings to make everything work. Had to add some material to steering stops, so turn radius isn't as tight.

[chugs]

Originally Posted by bitaria

Clipons are Vortex, and they sit below the upper triple, with controls rotated at a pretty steep angle down. I basically set it up the way I like and then cut fairings to make everything work. Had to add some material to steering stops, so turn radius isn't as tight.

Thanks, I currently have the woodcrafts clipons. I'm gonna slide them down the forks and see how it goes.

[bitaria]

Started on paint, or rather plastidip. Kawasaki should be green, but I didn't want to buy another tank or repaint this one - so plastidip. We will see how durable it is, worst case - easy to remove.

Here is a preview

[Foxrider64]

Love the color.

[sharky nrk]

definitely let us know how the dip holds up

[Tough Noogies]

The color does look fantastic!

I'm curious: how much extra weight do you think the plastidip added? In my head, it seems like it would be a lot, but I don't actually have any experience using it on something that large.

[bitaria]

Originally Posted by Tough Noogies

The color does look fantastic!

I'm curious: how much extra weight do you think the plastidip added? In my head, it seems like it would be a lot, but I don't actually have any experience using it on something that large.

I don't think it adds more than normal automotive paint... If anything should be easy to remove, but I hope it will hold up OK.

[redkid]

Originally Posted by Foxrider64

There is a lower lip on either side that has the ability to be bolted to the stock undertail. Hense another reason to keep the undertail.


The two indents on the top of the tail are for race subframes only.

What is this race subframe that you've been speaking off? Who makes it, and does anyone have any pictures?

[Foxrider64]

Originally Posted by redkid

What is this race subframe that you've been speaking off? Who makes it, and does anyone have any pictures?

I haven't actually seen any for sale- I have seen some custom made ones though.

[cbinker]

Originally Posted by bitaria

Made some progress!

Custom fairing stay mostly finished up, just need to add Vapor dash mount.

if you want to get rid of you key, i know a guy that makes a harness that re-routes the ignition to be turned on and off with the kill switch.

[daverdfw]

Originally Posted by cbinker

if you want to get rid of you key, i know a guy that makes a harness that re-routes the ignition to be turned on and off with the kill switch.

Who would that be? I am interested in doing that on my track bike.

[Somchai]

Originally Posted by daverdfw

Who would that be? I am interested in doing that on my track bike.

https://www.woodcraft-cfm.com/cgi-bi...4#General-Info

[cbinker]

Originally Posted by daverdfw

Who would that be? I am interested in doing that on my track bike.

https://www.facebook.com/arek.stanton?fref=ts
he'll make them for $20.

[sharky nrk]

^^ plug and play for $20? I would be in for one for sure. Glad to see Woodcraft is making one, but not sure I want to spend $60 on it.