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Discussion Starter #42
Thanks! It only took me four months of head scratching to come up with a R/W/B paint scheme working with the factory tank and fender color :) She wants to be able to street it sometimes, we'll see how much work it is and if she wants to help, ha
 

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Discussion Starter #43 (Edited)
Making stock Ninja 250 springs (0.65Kg/mm) into appropriate 0.75Kg/mm springs for Angie's CBR250.

Calculation, 0.65 x 30 (active coils) = 19.5 divided by 0.75 (desired spring rate) = 26.
Cut off four active coils, done. Another way to calculate is .65 divided by .75 = .8666 x 30 = 25.999.



Next I will take a brazing torch and heat the end in two spots so I can pinch it down flat and then grind it off nice. I measured 422mm as the original length, once I finish off the cut ends I will again measure and add the difference to my new preload spacers.
 

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Discussion Starter #44 (Edited)
Sorry I didn't take pictures of the bending and grinding stages, I suck for that. Basically a regular propane blowtorch is all you need, start about 190* from the cut end and heat it cherry red (oh, I also soaked a hand towel and wrapped the spring) then take some pliers and just pinch it down but not all the way flat. About halfway between that bend and the cut end do it again this time bringing it flat against the next coil. I used a common bench grinder to flatten it off the best I could, drop springs in fork tube cut end up followed by washer and preload spacer.

Calculating for new preload spacers: stock springs (422) plus 100mm spacers minus new spring length (353 for me) minus 16mm for Gold Valves (if you're using them) equals preload spacer length cut from 1" PVC pipe.
422-353=169-16=153mm preload spacer. YAY! $40.00 for 0.75Kg/mm linear rate fork springs.

I think the most you could get out of Ninja springs would be around .80Kg/mm, you can only cut so much off before you have spring bind. Don't quote me on the .80, you'll need to do your own math but there is 24 gaps between coils at about 9mm = 216mm so to be safe close to 200mm of compression without binding? I think that's right... Fork travel is only what 130ish so maybe you could go beyond .80

Here's something else to chew on, a lot of guys go to heavier oil and higher oil level to compensate for soft factory springs. I see a lot of guys carry this theory over when installing proper springs and I think it's wrong.

The heavier fluid is great and with emulators that's how you adjust the rebound, in this fork I am using 15wt Spectro. Spectro 15 and Maxima 15 are very close but if you want more rebound damping try BelRay 15 it's about 20% heavier.

The reason I think it's wrong to fill to or even above the factory recommended level is because the factory over fills to give you more air spring effect, this is to make the fork ramp up and somewhat reduce brake dive. They are also trying to compensate for the one spring for many riders issue. When you have the correct spring you do not need this nor do you really want it, all you really need is for the damping fluid to be covering the damping units. I'd say you can easily go 30mm below factory fill height, in my VTR I am filled to 160mm and factory says 124.
 

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Discussion Starter #49
The Rosso is tough to beat except for the sucky wear pattern of the dual compound rear. I tried BT-003RS on my VTR250 this weekend, they are OK but I didn't love them. Stiff carcass is nice under braking but there's a lot of feedback from the bumpy track.
 

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Discussion Starter #51
Has anyone compared the new S20 EVO to the Diable Rosso II yet?
Has anyone put a CBR1000RR throttle tube in the CBR250R? I can't remember if I tried it but I think I did and it didn't fit right.
 

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Has anyone compared the new S20 EVO to the Diable Rosso II yet?
.

Waiting for you to,
no excuse. they are $500 a set here in Au,
half the cost in your country.


That's why im going to order some 140/70-17 SC1 rears to AU,
Heaps of ppl here use Jake Wilson in the USA but cant find them yet.
 

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Discussion Starter #55
Waiting for you to,
no excuse. they are $500 a set here in Au,
half the cost in your country.


That's why im going to order some 140/70-17 SC1 rears to AU,
Heaps of ppl here use Jake Wilson in the USA but cant find them yet.
I have been waiting 5 weeks for them to become available again. Supposed to get mine next week. I was going to just say screw it and get some Supercorsa since they now have the 140 rear SC2
 

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If anyone can find me 140 supercorsas that do international shipping
SC2 is fine in our hot temps and abrasive tracks.


I need them for my MC22 as Phillip island is hard on tyres, an 150's only slow the little 4 cyl down.


Rocky mountain, Jake Wilson etc.. Im all ears.
 

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Not a chance with distributors, especially using Aussie servers from companies like Pirelli


Tyre companies, gear companies etc will direct us straight to out rip off warehouses (distributors)


Huge debates here about the topic of getting tyres online, but its got to the stage that we'e saving half if we buy the ideal amount of 3 at a time and keep it under $1000


*Ive spent more on tyres than I have on a cbr, a ninja and part of an R3 in the past 4 yrs.
 
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