Aussie XS400 Bratty Tracker Build

[jray]

Hi Guys, really pleased to find a dedicated XS400 forum! Ive already sourced some great info here so here is my 2 cents...

I purchased this XS250 on ebay about a year ago. I removed the 250 head and discovered a 400 cylinder block! What the?? It still ran well but was screaming for a 400 upgrade....

I have since done the following:

- replaced the clutch, I ordered plates and springs from http://www.wemoto.com/
- bought a donor XS250 Special (minus the engine) and swapped the current rear 18" wheel and disc brake with the 16" rear wheel and drum brake. This will allow for a fat walled tyre and the drum brake visually looks much cleaner.
- I found a 400 head which is a very rare find here in Australia!!! Currently reconditioning, found NOS valves on ebay which have been fitted.
- had a 400 head gasket fabricated in copper.
- purchased an R1 'Blue Spot' caliper to upgrade the front brakes, as inspired by other threads on this site.

and with the help of very basic skilled photoshop, this is kinda where im heading, minus pretty paint etc.....


- extend swingarm 2" and extend rear shocks.
- relocate battery box to underside of swingarm area.
- new brake caliper, caliper bracket, disc and master cylinder.
- new short mega exhausts, pod filters and rejet carbs.
- new seat, rear tail light and rear fender.
- new bars, switches and headlight.
- powdercoat and paint!
- and last but not least, do I use the stock tank or find an alternative? Id like something slimmer and smaller as the stock tank is so bulbous! I have an old tank and like the knee dent thread, but not sure I can hammer for that long....

 

[ahale2772]

I think a square tank would look cool on there, expecially with the open area under the seat and a slim seat cushion, they are a bit smaller also

 

[crush1776]

Welcome to the forum, your list of mods is respectable. I agree with ahole, i mean er ahale , the 400 standard tank is the easiest tank upgrade and "looks the business" as they say!

My example:

 

[bcware]

I really like that style tank; I am happy it came on mine

 

[ahale2772]

ahole? lol you must be talking to my buddies, that nickname stuck in the 6th grade

 

[crush1776]

ahole? lol you must be talking to my buddies, that nickname stuck in the 6th grade

Obviously just busting your chops my man! I've had a few in my day as well, I'm glad "Lush Crush" didn't last to long!

 

[ahale2772]

Lol, Takes a bit more to ruffle my feathers

 

[hardtailed77]

Welcome jray! Sounds like you have a pretty good game plan, so be sure to stick around and keep us updated.....WITH PICS!! WE LOVE PICS!!! haha

 

[CadXS]

Welcome to the forum jray Looking forward to seeing how this one goes together.

 

[drewpy]

welcome Jray, good ideas there, glad your sorted on the 400 engine, much better IMHO

 

[jray]

Thanks for the welcome guys! Yep, very happy its almost a 400, im guessing performance wise it was probably running halfway at 325cc with the 400 cylinder block and the 250 head....just not quite there...

Not sure about the standard square tank, I think this suits a cafe racer style with a rear tail rather than the long seat and fender. Thoughts?



and I went past the wreckers this afternoon and picked up a nice tasty bit of kit from a Ducati Monster 620. Couple this with a radial master cylinder and it should pull up pretty damn quick!

 

[Pork Chop]

Welcome Jray,

Good to see another Aussie on here. So your bike was all xs250 except for the xs400 jugs? I have the xs250 and thinking about doing the jugs and head conversion and will be interested to see how you go. Keep the updates and pics coming.

Have you thought about an old yz80 tank? Might need some work but could be interesting.

 

[ahale2772]

your right on the tank, with nothing but a rear fender it looks weird, id say find something like what Drew has on his flat tracker

I like the huge front disk

 

[drewpy]

Thanks for the welcome guys! Yep, very happy its almost a 400, im guessing performance wise it was probably running halfway at 325cc with the 400 cylinder block and the 250 head....just not quite there...

Not sure about the standard square tank, I think this suits a cafe racer style with a rear tail rather than the long seat and fender. Thoughts?

View attachment 4445

and I went past the wreckers this afternoon and picked up a nice tasty bit of kit from a Ducati Monster 620. Couple this with a radial master cylinder and it should pull up pretty damn quick!

View attachment 4446

250 head valves are way too small

either get the head machined and squeeze in bigger valves or look for a 400 head.

this is an xs450 that was on german ebay a few years ago!

 

[crush1776]

Great, now you guys have me all self conscious about my build . I suppose it depends on the angle of the photo and how thick your seat will be though: kneeling down looking dead on sideways like your mockup it looks choppy, but...

And I think mine will look ok with about a 2" thick seat:

 

[hardtailed77]

250 head valves are way too small

either get the head machined and squeeze in bigger valves or look for a 400 head.

this is an xs450 that was on german ebay a few years ago!

Holy speedholes Batman!!!!!

 

[ahale2772]

the square tank would look lame with no seat or fender, with 2inces it will look lots better

i really like this pic of my bike when, it had no rear anything the bigger tank tapers down nicely in the back...

but then again it looks HUGE and makes the rest of the bike look small

 

[hardtailed77]

Stretch the swingarm and that will take care of the look!

 

[ahale2772]

I plan too , once I solve all its gremlins

 

[jray]

Good to see another Aussie on here. So your bike was all xs250 except for the xs400 jugs? I have the xs250 and thinking about doing the jugs and head conversion and will be interested to see how you go. Keep the updates and pics coming.

Have you thought about an old yz80 tank? Might need some work but could be interesting.

Hey Pork Chop, also pleased to find another Aussie! An XS400 top end will bolt straight onto the 250 bottom end. Mechanically its the only difference and a very straight forward swap. The hardest part will be finding a 400 top end here in Oz, ive had daily searches on ebay for over a year and I havent seen a single listing. There are plenty on ebay USA but they all have round fins (Australian models featured square fins) and I wanted to match the square fins on my existing cylinder block. So I dare say youll need to find one in the USA and fork out for reasonably weighty freight. One piece of advice with your searching is to ensure the head and rocker cover have matching serial numbers as they were line bored and must be a perfect match.

Has anyone fitted a YZ90 tank? If so what year?