AR125

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ar125josh
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Post by ar125josh »

Ok thanks will do, Im still yet to create a photo bucket account but have made a start on one engine will try post some pictures soon.
How did you find the parts in those countries. ?

I have been looking on yahoo auctions japan and they have a fair few bits over there, we just dont have yahoo auctions in the uk.
TwoStroke Institute
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Post by TwoStroke Institute »

Carburetors.
Go straight to a VHSB Delorto 30mm off a ICC kart, disc valve motors love them.
Head go to 10.5cc 13.5:1 comp with a 6mm squish band and 0.8mm gap.
Keep the exhaust port low as possible . Run on 98 fuel only.
Move the disc on the spline so you close(trailing edge) the inlet at 75-80deg ATDC.
For a start that will fly
crochet & croquet
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Top-shaggy
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Post by Top-shaggy »

Reliability TSI ??
I'm using a KR1S carb on one at the min - They like them too !!
Cost wise, second hand KMX VM26 is a great starting point as the original AR carb is too rare :D
If it takes more than 2strokes then your just playing at it..
TwoStroke Institute
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Post by TwoStroke Institute »

That's a safe set up running 98 fuel
crochet & croquet
pepsi
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Post by pepsi »

just bought a 1981 KE125 for runnning around the campsite, I thought it was close to the KR250 halved :?:
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Top-shaggy
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Post by Top-shaggy »

pepsi wrote:just bought a 1981 KE125 for runnning around the campsite, I thought it was close to the KR250 halved :?:
The AR125 engine definitely shares the same DNA as half a KR250A

The KE125 looks more like the KH air cooled engines to me?

That said, bet it's fun zapping around the campsite, the AR certainly would be no fun off road :D
If it takes more than 2strokes then your just playing at it..
pepsi
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Post by pepsi »

The KE125 is disc vlv'd
Top-shaggy wrote:
pepsi wrote:just bought a 1981 KE125 for runnning around the campsite, I thought it was close to the KR250 halved :?:
The AR125 engine definitely shares the same DNA as half a KR250A

The KE125 looks more like the KH air cooled engines to me?

That said, bet it's fun zapping around the campsite, the AR certainly would be no fun off road :D
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Top-shaggy
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Post by Top-shaggy »

pepsi wrote:The KE125 is disc vlv'd
Top-shaggy wrote:
pepsi wrote:just bought a 1981 KE125 for runnning around the campsite, I thought it was close to the KR250 halved :?:
The AR125 engine definitely shares the same DNA as half a KR250A

The KE125 looks more like the KH air cooled engines to me?

That said, bet it's fun zapping around the campsite, the AR certainly would be no fun off road :D
I suppose what I should have said is that the AR125 was evolved from the back-pot of the KR250 and shared the same disk valve system (which kept the induction distance to a minimum). Many other bikes had disk valves such as the suzuki's of the same era etc

But I do like the KE125 and it's a bike I would like to own one day :D
If it takes more than 2strokes then your just playing at it..
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the KR kid
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Post by the KR kid »

My very first bike was a brand new metallic blue KH125 in 1978, the year they came out. Same engine as the KE. Absolutely brilliant little bike, and would love to own another one; but not the shape of the KH125 that replaced it. Engine was so easy to work on; I rebuilt the engine in the morning and part-exchanged the bike for a new KH250B-5 in the afternoon!
Stop annoying me, I'm running out of space to hide the bodies!

GS750B
KH250B5
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Top-shaggy
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Ar125 pistons - differences between models

Post by Top-shaggy »

I was asked the question - what's the difference between the early AR125 (82-84) and later (post 85 model) pistons ?

Well I've had my measuring stick (vernier) out looking at two pistons from each period and the answer is.......

De de dum . . . Pretty boring really

Hardly anything other than the Kawasaki part numbers and the strengthening ridges cast under the head of the piston:

The piston on the left is a A model (not restricted) piston from 83/84 model whilst the one on the right is a A model piston from circa 1988
Image

Image

Single reinforcing ridge 83/84 piston
Image

Three reinforcing ridges 88 piston
Image

I also checked a couple of cheaper pattern pistons advertised for all models (all years 82-91) and these had the single reinforcing ridge.

Conclusions - not a lot of difference.
Pistons that are oversized (+1mm/+2mm etc) are the same as the standard pistons from each period group.

If choosing a piston I would opt for the later A model genuine KHI piston
:wink:

CC from my post on DS site
If it takes more than 2strokes then your just playing at it..
Toot...
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Post by Toot... »

Good works TS =D>

I can now start the search for a bargain :P
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Top-shaggy
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Re:

Post by Top-shaggy »

TwoStroke Institute wrote:Carburetors.
Go straight to a VHSB Delorto 30mm off a ICC kart, disc valve motors love them.
Head go to 10.5cc 13.5:1 comp with a 6mm squish band and 0.8mm gap.
Keep the exhaust port low as possible . Run on 98 fuel only.
Move the disc on the spline so you close(trailing edge) the inlet at 75-80deg ATDC.
For a start that will fly
Hi TSI

How are you getting on with the AR125 Barrel, Head and Piston combo that I sent you?
Did you ever get your engines from Japan?

Cheers :roll: :wink:
If it takes more than 2strokes then your just playing at it..
TwoStroke Institute
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Re: AR125

Post by TwoStroke Institute »

Slow going mate, that cast iron is crap to work with , in so much as most of it ends up in my nose and all over my face. I be getting back to it after this week. My AR motor is coming out in the boot of a car so I just have to wait.
crochet & croquet
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