AM Kit 025 build 250 quad port top end

[Naked Arborist]

This thing runs like no other 025/250 I have ever handled after only 2 tanks. Some numbers taken from the AM kit and the OEM. Some are mm and some are inch measurements. Don't ask, just the way I do things.

AM/OEM

wrist pin end play spec is 0.010
0.020/0.008

Wrist pin size
0.391/0.390

flat top to wrist pin bore 13mm

quench, squish
0.036-0.040 average 0.038 AM
0.052-0.058 average 0.055 OEM

piston skirt thickness
intake 1.20/1.50 mm
exhaust 1.75/1.56 mm

AM piston has a overall 0.020 taper from widest to crown.

AM rings were a nice cast set gaped at 0.008 0.0095

AM piston skirt to crank counter weight clearance 0.075 on both sides

AM outside ports sizes out of the box
exhaust width 24.1/ height 16.7 mm 0.030 wider than OEM
intake width 21.3/ height 16.75 mm 0.005 wider than OEM

Compression is at 130psi and sure to climb with use.

The intake roof entry angle is 10 degrees higher on the AM jug. Most everything else can be considered well with-in spec. :msp_biggrin: The fit and finish of this kit was good IMO. The plating was decent. The ports were nice and had plenty of meat in them all around. One last note, the combustion chamber is keyhole shaped in this kit.

I have many more pics. Most are blurry.

 

[Naked Arborist]

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[watsonr]

Very nice review on the kit! Looks pretty good, numbers are good... seat of the pants you say is great. Think you got a good deal! Make sure the impulse nipple is sealed where it joins the cylinder, most are just pressed in.

You know the next question... where did you get it and how much?

 

[Naked Arborist]

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[Naked Arborist]

Very nice review on the kit! Looks pretty good, numbers are good... seat of the pants you say is great. Think you got a good deal! Make sure the impulse nipple is sealed where it joins the cylinder, most are just pressed in.

You know the next question... where did you get it and how much?

I'm getting to that lol. I need to call my partner for the cost. He is over at the shop I think. The kit came from HLSupply.

Did you get those Makita BB's yet?


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[watsonr]

I'm getting to that lol. I need to call my partner for the cost. He is over at the shop I think. The kit came from HLSupply.

Did you get those Makita BB's yet?


Seg 4

Though so, send me a PM about this kit and the 7900?

 

[H 2 H]

I built a 250 the beginning of last summer with parts I got from watsonr partner

I didn't do all the picture work as you did but it's a strong runner for it's size and has several gallons of fuel thru it

One thing I found that made a difference was a WT 215 and a good MM


PS: I did do some simple mod's the the cylinder ports

 

[Naked Arborist]

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Pretty sure the middle two intake pics are OEM cld.

 

[watsonr]

I built a 250 the beginning of last summer with parts I got from watsonr partner

I didn't do all the picture work as you did but it's a strong runner for it's size and has several gallons of fuel thru it

One thing I found that made a difference was a WT 215 and a good MM


PS: I did do some simple mod's the the cylinder ports

Same kit, he gets them same as I do. I carry that WT215 carb now.

 

[Naked Arborist]

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[watsonr]

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Combustion chamber looks good. Last one had injection marks from the coating inside the chamber. Didn't hurt anything, raised compression I'm sure. Compression is 130, should come up some, maybe another 10-15lbs. But if its a runner, its a runner. I've always felt that number was overly relied upon to determine if a saw runs good or not. Seen many a saw run very good on lower numbers than some believe are a good acceptable number.

 

[Naked Arborist]

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seg 7 Had a phone call lost track. Heading out to go sell some tires. Will post up more picks later. Might give you a peak at the port work :tongue2:

It'll be wet but I'll grab a video of the saw in action while I'm over there at the shop.

7:05 PM. Still waiting for the invoice price and the video to come in. PM box is open now. Eating dinner then I'll be back.

 

[Naked Arborist]

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Just some random comparisons. Easy way to figure quench with out crushing or squeezing anything.

I'm done for tonight. Going out with the wife for a change. Have fun!

 

[hitechredneck]

I'd like to rebuild my older 025 with this kit plus any carb tunes required.

Sold my MS260 to cover some costs plus I often have guys with larger saws surprised at my little 025 in the field.

Mo power please..

 

[watsonr]

I'd like to rebuild my older 025 with this kit plus any carb tunes required.

Sold my MS260 to cover some costs plus I often have guys with larger saws surprised at my little 025 in the field.

Mo power please..

Send me a PM when your ready for the kit.

 

[Stihlofadeal64]

I take it you are selling these MS250 kits also. PM me with a price or post it here - which ever works for you. I'm not sure in the other thread if I received the price for the MS390 kit as well. I build quite a few saws, (no porting) but sell my share as well. Thanks

 

[Naked Arborist]

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[Naked Arborist]

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[watsonr]

I take it you are selling these MS250 kits also. PM me with a price or post it here - which ever works for you. I'm not sure in the other thread if I received the price for the MS390 kit as well. I build quite a few saws, (no porting) but sell my share as well. Thanks

PM sent

 

[Naked Arborist]

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More pics tonight, the phone rang estimates

The good stuff is coming tonight. Stay tuned...