Ke125

**richban** · 11th March 2014, 19:04

Originally Posted by cotswold

I took a little look and although no expert I reckoned it was all too hard front and back.

Start with springs and work back. Without the correct spring rate you are screwed.

For the rear I run 27-28 with me on it. And about 5 with just the bike. Front 15 bike only 35 - 37 with you on it. No expert at all but my 2 cents.

**kel** · 12th March 2014, 15:30

Thanks for your input guys, especially Gary and Tim who had a play with settings on the Saturday night. The bike definitely responded to the extra compression dampening in the rear, it turned the squat and spin in to more of a slight drift which was pleasing, bloody front end still let go though.
I've downloaded info on settting, aligning and measuring everything so I'll work through this then hand it over to someone for final (if there is such a thing) set up.

Yes 94 forks Scott, I liked the colour of the shiny turny things not that I know how to use them. Man you were on fire last weekend.

Koba you maybe right as the old FXR use to feel like it would slide and cross up like a speedway bike, RS just goes down.

And Rich how's your shoulder. Looked like a fairly solid impact when you went down.

**richban** · 12th March 2014, 15:47

Originally Posted by kel

And Rich how's your shoulder. Looked like a fairly solid impact when you went down.

Shoulder fine thanks. The pain I am in is from a big moment on Saturday. More hurt from staying upright than hitting the deck. How does that work!

**mr bucketracer** · 12th March 2014, 16:26

did not seem to give you any warning rich ? i think part of why i went quicker was my bike was not much less than rich's on the dyno so realy all up to me to pull finger like i was riding my old 400 lol . i did know i was not going to last but thought i will go untill i'm buggerd . think some high bars would help me though. wish i had your build kel

giving away55-60 kg's to the leader done not help

**kel** · 20th January 2015, 18:55

So the bike had a bit of a meltdown last weekend. Had been running super well, but it seemed I over heated it and it had a heat seizure.
Sure looked like it on first inspection

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But once I pulled the barrel off I was somewhat confused with what I was looking at

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A broken ring? Nope, the bloody ring peg had let go (ring pegs have it in for me) and the ring had spun around, eventually snagging in the exhaust and BOOM. Expected better from an unmodified Wiseco piston but there you go
Its a mess, bits of ali all through the ports and down in the cases. And look at the black mess in the crankcase transfer channel, I figure that's the exhaust blowback through the hole in the piston.
Oh well, full rebuild time for this motor. Not too sure I want to use another Wiseco piston.

**F5 Dave** · 20th January 2015, 19:13

Yeah would have to say that is unusual. Have a good look at how symmetrical your ex port is and chamfer so it isn't fretting the peg.

**speedpro** · 20th January 2015, 21:26

more than one problem there. Possible port symmetry problem as Dave says but something caused that fizzling of the piston. I've found excess heat caused that on an otherwise OK motor, in that case a sleeved down RGV250 cylinder on a full crankcase reed TS100 with a not quite good enough water pump.

**kel** · 20th January 2015, 21:53

Originally Posted by speedpro

something caused that fizzling of the piston.

Fizzling? No idea what that is.
Exhaust port symmetry is fine, spent days on the bastard to get it just right.
Motor looks like it was running super lean, colour in the exhaust duct and header was a very, very pale grey, it looks like some sort of ceramic coating. The jetting wasn't that lean so Im thinking air leak

**F5 Dave** · 21st January 2015, 08:17

Looking at that piston again I don't think you can blame the piston, its been eroded, melted, mullered & erm, fizzled

**Yow Ling** · 21st January 2015, 10:11

Is this the air cooled thermal instability problem Frits is always concerned about ?

**F5 Dave** · 21st January 2015, 13:28

I'd say leakdown test & also forensically check jets in your carb

**kel** · 21st January 2015, 14:32

Originally Posted by Yow Ling

Is this the air cooled thermal instability problem Frits is always concerned about ?

I would think so. It was a very hot day and I was guilty of over revving the poor thing.

So now I have to decide what to do. The new cylinder has not materialised and the builder seems to be side tracked, so ...
Rebuild the air cooler, crank and all, plus make the new head?
Cut the aux exhausts into the RG cylinder and go 100 water cooled? Cases and crank are ready to go.
Or buy that 94cc Derbi kit and graft on to the spare KE bottom end - Im leaning towards this due to the ease of sourcing affordable quality parts

**Bert** · 21st January 2015, 20:35

Originally Posted by kel

I would think so. It was a very hot day and I was guilty of over revving the poor thing.
So now I have to decide what to do. The new cylinder has not materialised and the builder seems to be side tracked, so ...
Rebuild the air cooler, crank and all, plus make the new head?

Real bugger but also provides for an exciting development adventure.

Originally Posted by kel

Cut the aux exhausts into the RG cylinder and go 100 water cooled? Cases and crank are ready to go.

My vote is for this option, it's been done and works very well, I'm sure Jason will pop in and share his two cents on his success.

Originally Posted by kel

Or buy that 94cc Derbi kit and graft on to the spare KE bottom end - Im leaning towards this due to the ease of sourcing affordable quality parts

Didn't think they produced a non-performance/racing 94cc kit?

Don't mind me, I just think this entire derbi bigbore route really is a piss take (and so very grey under the current rules) given the endless fuss about MX85 motors....