TS250x tidy up

[SON]

After sand blasting check the frame for cracks just above the pivot point for the upper suspension linkage they can crack there just above the gusset.

Yes I forgot to mention that
If it hasn't cracked it eventually will
So gusset it before paint powder coating?
.
I was never a fan of Wiseco pistons in the TS but they did have some specials that went to 285cc for the E model and the 85 LT250 Quadracer
I have not seen them for years

[nelpd96]

After sand blasting check the frame for cracks just above the pivot point for the upper suspension linkage they can crack there just above the gusset.

Good to know will give it a quick clean up and pop some having in there in the morning before work.

[LWC82PE]

These may also suit if you can find some (no longer made)
Progressive suspension springs for 38mm forks

Progressive Suspension USA #11-1138
Spring length – 533mm
Spring OD – 31mm
Spring wire dia. – NA
Spring rate – Progressive – 0.32kg/mm – 0.50kg/mm (18lbs/in – 28lbs/in) #11-1138 - 18/28 lbs - 533mm long - 31mm OD 

the application sheet that came with the springs says they fit
and i think they had PVC spacers in the box??

KDX200 - 83-85
NX250 - 88-90
XR250 - 84-85
PE175 - 82-84
RM125 - 82-83
YZ125 - 83
KDX250 82-83

So looking at the NX250

in other Euro brands easily found they match up to these.

White Power (WP) #9932.0079.A
Spring length – 585mm
Spring OD – 31mm
Spring wire dia. – 4.4mm
Spring rate – Progressive - 0.33kg/mm – 0.54kg/mm (18.43lbs/in – 30.16lbs/in)

Wilbers #600-0197-00

Promoto #500-0197-00

Wirth # 2060 (FNR13196)

Ikon #500-197

Hagon #400-197-00

You can also fit air caps. I am pretty certain 79-82 RM or 82-84 PE175 caps will fit. I can check for sure if you want to know but it was something i looked at myself 6 months ago and i am pretty certain the RM/PE caps would screw in. I only eyeballed them and did not actually do a test fit though.

[Andrew L]

Very hard to see future cracks or undetected ones through powder coating until to late and hard to repair cosmeticly afterwards, two pack paint or even rattle can a better option only my opinion but worth considering that's the way I'm leaning towards

I know some consider this bike a bit soft, but the info on here is invaluable to us that don't cheers blokes keep it coming

[nelpd96]

Big thumbs up to this place I have to say. The willingness to share information about these relatively unknown bikes (in a modified/ Vinduro sense) is just fantastic.

Mav, like I said I will bang some gussets in there before taking the frame in just to make sure that it will stand up to any future cracking.

LW, those spring rates for the progressive stuff should be spot on. Given how easy it is to drop the forks I will probably be doing those towards the end of the tidy up at this stage but air caps would be a nice edition to provide some extra tunability.

I will get some photo up tonight of the rear shock with the 5kg spring in there if I have time to get it back together tonight and I can work out how much oil is supposed to go in there and how to get it in  The stuff that came out looked about 30 years old......

[nelpd96]

Well guys as you said there was a crack in the frame on the right had side. All sorted now, didn't end up with extra bracing in there given the location I just figured that if it goes again I will have to weld it up once more. The frame came up reasonably well even though I think the colour is a little light compared to the factory blue. Not much I can do about it though as the only other blue they had was pretty dark. The rear swing arm came up ok I am tempted to send it off for a sand blast and get it re coated but the budget is just about blown already with the parts tally up over $600 already.

I have not been able to find enough info on the rear shock to give me a chance at doing the oil and gas so decided to bite the bullet and send it off to RADS. That will be going in the mail tomorrow with an estimated one week turn around for me to work out the motor prior to putting it all back together. The rear guard support, number plate bracket kick stand and battery tray were powder coated as well but needed to be redone as they were the same blue as the frame rather than the satin black that I asked for.

[nelpd96]

Ok so managed to pop the lid on the engine today to see what sort of condition it was in. The thing is not too bad but there is room for improvement. The squish band is sitting at around 3mm clearance so I will be taking 1.5mm out of the head to bring that down as well as looking at the compression ratio. I also ran some numbers on the exhaust port duration ect. and mine standard is sitting around 178 degrees but the piston also sits around 2mm high of the base of the exhaust port so if I trim a little from the top of the piston to uncover the exhaust port a little earlier that should help things along. 1mm off the piston will add around 3 degree's of duration.

Also based on an exhaust duration of 180 degrees and peak power at around 7500rpm I am looking at an exhaust length of around 1020mm which is pretty close to what we have with the standard pipe so I have opened that up and removed the offending bits and pieces in that and welded it back up as well. Will rip the barrel off tomorrow and clean up the ports and the piston while I wait for the boysen reeds to turn up and start putting the other bits and pieces back together. I will take some more photos tomorrow to add to the collection.

Cheers
Paul

[Andrew L]

Did you have to get swingarm bearings/bits  mine are toast haven't been into try for any yet are they still available

[nelpd96]

Mav at this stage I have not had to replace anything less the head stem and wheel bearings. Judging but the condition I would say that they have not long been done. Even the swing arm bolt came out with just a tap.

Grab the part number from cmsnl and see if it matches any other bikes.

[80-85 husky]

match your transfers to the base gasket and look to smooth any sharp bends in the transfers, usually gives a good boost to the mid range. with the pipe and other mods, it should pull better than the anemic tug they arrived in the country with.

[suzuki27]

Hi, just thinking 1.5mm sounds like a lot to take off head.

[nelpd96]

Hahaha it does to me as well so here we go.....

I just cc-ed the combustion chamber and for the players at home. It is coming in at around 26.5cc including the head gasket thickness. This returns a compression ratio of 10.4:1 which is pretty bloody low so taking the 1.5mm off that I need to bring the squish back into spec will bring it up to 13.0:1 which is getting up there but on a water cooled engine and running 98 is should be fine. Along with the other stuff I am hopeful of this thing actually feeling like it has some grunt. Full gasket kit turned up today....trying to resist the urge to split the case at this stage give that it was running fine before hand. Will check the sizing of the bore tomorrow to order a new piston and rings. Like I said before I am probably going to try a couple of things with the old piston before dropping the new one it. Not withstanding all the other bits turning up in a reasonable time frame I should have it all up and running before the end of the month.

[80-85 husky]

Nice open heart pipe surgery there Dr Barnard that should open er up a bit and get some good old "dinga de ding ding dinging" going when you fire her up!!

[SON]

You are close to the money
I am starting to remember 2.3mm off then machining a fresh squish
I had it written but a move of the shop wrecked finding that

[nelpd96]

SON, that would be a better idea as the squish on the head is not parallel to the piston face judging by the cross section of the putty that I used to check the squish. Also the squish band is not quite 50% so could be a little larger which you would be able to do if you took the lot off and started again. That it is a little too much for what I have planned for the engine though. From what I can gather the 3mm is not really tight enough to be a squish at all, it is also going to be larger than that in reality because I left the carbon on the top of the piston to give me some room for error.

Either way I will be taking to my friendly machinist tomorrow to confirm and run the head back in the lathe. I will do a 1mm cut to start and see how it looks and bring it down from there.

Hopefully at least this info will help others that want to play with these things in the future.

Cheers
Paul