High Quality Chainsaw Bars Husqvarna Toys Hockfire Saws

Husqvarna 254XP Rebuild

XP_Slinger

They’re Just Saws
Local time
3:48 AM
User ID
845
Joined
Feb 9, 2016
Messages
6,089
Reaction score
27,524
Location
Central NY
Country flag
Well, after looking over a few 254 build notes, I have to say that I'm getting most of the port timing changes from the machining of the cylinder. Which really won't do you much good. Sorry :(
Those cylinders are timed very well right out of the box imo. Without a base and chamber cut I can see performance going a little backwards.
 

ZukiRyder400

Breaker of recoils
Local time
3:48 AM
User ID
5876
Joined
Apr 11, 2018
Messages
1,003
Reaction score
4,243
Location
NY
Country flag
Well, after looking over a few 254 build notes, I have to say that I'm getting most of the port timing changes from the machining of the cylinder. Which really won't do you much good. Sorry :(
Thats fine:).
 

huskyboy

Sorta a husqvarna guy...
Local time
3:48 AM
User ID
1352
Joined
May 30, 2016
Messages
10,025
Reaction score
43,459
Location
Ct
Country flag
I decided to not touch the ports in the mahle 262 cylinder after rattler decked the cylinder to optimize the squish. I saw they were widened to near max width factory. Saw seemed to run good for a small saw. The little bump in compression seems to help the torque of small saws. Looking at your photos I’m surprised how much smaller the lower transfers were in the 254 cylinder stock vs the stock 262 cylinder. What’s the difference in displacement 5 cc or something like that?
 

PA Dan

Mastermind Approved!
Local time
3:48 AM
User ID
306
Joined
Dec 28, 2015
Messages
7,025
Reaction score
34,623
Location
White Oak PA
Country flag
I decided to not touch the ports in the mahle 262 cylinder after rattler decked the cylinder to optimize the squish. I saw they were widened to near max width factory. Saw seemed to run good for a small saw. The little bump in compression seems to help the torque of small saws. Looking at your photos I’m surprised how much smaller the lower transfers were in the 254 cylinder stock vs the stock 262 cylinder. What’s the difference in displacement 5 cc or something like that?
What cylinder was it Mason? I have KS and a Mahle decomp. The last one I built had a Mahle non decomp. I used a thinner gasket to get the squish to .019 and that saw was awesome.
 

ZukiRyder400

Breaker of recoils
Local time
3:48 AM
User ID
5876
Joined
Apr 11, 2018
Messages
1,003
Reaction score
4,243
Location
NY
Country flag
I decided to not touch the ports in the mahle 262 cylinder after rattler decked the cylinder to optimize the squish. I saw they were widened to near max width factory. Saw seemed to run good for a small saw. The little bump in compression seems to help the torque of small saws. Looking at your photos I’m surprised how much smaller the lower transfers were in the 254 cylinder stock vs the stock 262 cylinder. What’s the difference in displacement 5 cc or something like that?
I honestly thought the 254s were about the same size as the 262. I was very surprised muh self. The 262 has a slightly larger bore and slightly longer connecting rod. I think the displacement difference is right around 5cc.
 

huskyboy

Sorta a husqvarna guy...
Local time
3:48 AM
User ID
1352
Joined
May 30, 2016
Messages
10,025
Reaction score
43,459
Location
Ct
Country flag
What cylinder was it Mason? I have KS and a Mahle decomp. The last one I built had a Mahle non decomp. I used a thinner gasket to get the squish to .019 and that saw was awesome.
It’s got a mahle decomp cylinder. Unfortunately the serial number was worn off on the first few numbers so I can’t see what year it is. Had a 120 carb so I assume later production.
 

huskyboy

Sorta a husqvarna guy...
Local time
3:48 AM
User ID
1352
Joined
May 30, 2016
Messages
10,025
Reaction score
43,459
Location
Ct
Country flag
I honestly thought the 254s were about the same size as the 262. I was very surprised muh self. The 262 has a slightly larger bore and slightly longer connecting rod. I think the displacement difference is right around 5cc.
Do 262 cylinder lowers vary? They were huge on this mahle decomp cylinder. Like almost the size of 660 stihl lowers.
 

huskyboy

Sorta a husqvarna guy...
Local time
3:48 AM
User ID
1352
Joined
May 30, 2016
Messages
10,025
Reaction score
43,459
Location
Ct
Country flag
This is the only photo I have of it after rattler cut the base and cleaned up the squishband that got damaged by bearing failure. You can kind of see the width of the lowers that I circled. 1AA2C49E-9B0B-4D3E-ABE8-7B3964FCE132.png
 

PA Dan

Mastermind Approved!
Local time
3:48 AM
User ID
306
Joined
Dec 28, 2015
Messages
7,025
Reaction score
34,623
Location
White Oak PA
Country flag
Do 262 cylinder lowers vary? They were huge on this mahle decomp cylinder. Like almost the size of 660 stihl lowers.
Yes...here is the KS cylinder. It was different from the Mahle non decomp from what I remember.
01d5b3a9db226237b76155b2b92613ff.jpg
 

XP_Slinger

They’re Just Saws
Local time
3:48 AM
User ID
845
Joined
Feb 9, 2016
Messages
6,089
Reaction score
27,524
Location
Central NY
Country flag
Both models are true in displacement to their respective model numbers. 8cc difference between 254 and 262.

I’ve had my booger hooks in Mahle and KS cylinders and the transfers mirrored what you guys are observing. KS has tighter uppers when compared to Mahle.
 
Top