Best RPM for a 268xp ?

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GWJ

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Just getting a consensus, as to what's the best RPM to run a 268xp at? My manual states 13300 as the max RPM. Just wanted to see if anyone runs it lower or higher, or just at 13300?
 
No need to go higher than 13,000. I don't think it's a good idea to set them right at the max.
 
Revive an old thread? Or start another one? What IS the true max no load RPM for 268XP? I have not seen the 13,300 figure. 12,500 is what I find. I have asked Husky tech this question several times. Some very good knowledgeable people. But they all say they can't answer why 12,500 for this saw, and 13,500 for the 272XP that is this saw with a larger cylinder and piston.
Husky changed the crankshaft, flywheel and coil in late 93. But my research shows they changed the RPM when they introduced the 272XP. I read a lot on this site, but post very little. I read enough to know there is a vast amount of knowledge available from the members. Probably nowhere better to ask this question. I would really appreciate if someone will explain this. And why the 1,000 rpm difference in the two saws. If anything, I would have thought the heavier 52mm piston would lower Max no load. I know there are those who will say what difference does it make. Tune it in the cut. But it does make a difference. Should all max no load data and tachs be thrown out the window? Will somebody please explain this to me? Thanks.
 
Interesting question. I doubt anyone know for sure why. Is the 268 a quad port cylinder? Maybe if it's a duel port and the 272 switched to a quad port that would explain it... intuition tells me that the 268 is/was a quad port the whole time (as well as the 272). I wonder if it has to do with the ignition in that case... idk, I'm interested to hear what others think.
 
I really don't know but if I had to guess I'd guess its the port timing and the 272 is timed to rev higher.
If a saw is timed to make peak power and cut at 10000rpm why turn it up to 13500 max rpm, it wont cut any faster, it will still cut at 10000.
 
I usually go by ear rather than spec on older saws and keep the rpms at a moderate level when adjusting under no-load condition... the final cutting test is more important. No use to set to a high no-load speed if the actual cutting performance is no good with that setting. If I feel I need more rpms in the cut I just tune H a little leaner when cutting with the saw.
 
If a saw is timed to make peak power and cut at 10000rpm why turn it up to 13500 max rpm, it wont cut any faster, it will still cut at 10000.
Unless I've misunderstood, the answer is that you set the mixture so that the engine multi-strokes at 13,500rpm without a load, in order that the correct mixture is delivered to safely provide maximum power at 10,000rpm when fully loaded.
 
13,300rpm seems about right.
These figures from the 2001 61/268/272XP Operators Manual. I understand that this is not the XP version 268XP which I am told has a cylinder and piston of the same type as the 272XP whereas the non-XP 268 has the same Gilardoni hybrid-port cylinder and piston as the 66, which would account for the difference.

___________________________61________268/66______272XP
Recommended max. unloaded rpm_12,000_______12,500______13,500
Maximum Power(kw)@rpm_____2.9@8,300___3.2@9,000____3.6@9,300
 
There is enough play in flywheel keys that proper installation of flywheel could vary 1°-3°+ quite easily. That being only one factor that can effect max rpm quite bit & means that spec sheet data should be a guide, every saw will be slightly different. How well do you like your saw tuned? I tune for best performance & not some arbitrary number. Most saws out there are not that well tuned at all that includes new saws freshly tuned from a dealer.
 
I think the difference is non existent.....the spec for the non XP268 (open port Gilardoni P&C) is 12,500 The 268 XP is 13,500 as is the Jonsered 670 Champ which has the exact same P&C as the 268XP...the only difference is how the impulse is directed to the carb and the intake system. The porting, transfer sizes/shape , port timing, and pistons are as close to being the same as production will allow.
 
Okay. Thanks for the input everybody. The spec sheet I see says 12,500 max no load for 268XP with 4.7 h.p. The 272XP 13,500 with 5.2 h.p. I feel the factory max no load is a good starting point. I'm a bit conservative and usually cut the saw 200-300 RPM. I'm of the mindset of Husqvarna hotellgast. Nothing is perfect, but with Max no load set near spec, max loaded rpm should then be close. I just don't understand such a big jump in RPM. 2 or3 hundred maybe. But a 1,000 rpm difference? I do feel max no load is important to keep from over revving a saw. Crank, bearings, cases built for just so much. I'm not trying to switch gears, but for example, when I tune a 372 X Torque, I keep it at 13,000. Even though it's rated at 13,300. I don't think the cases will last long at anything more than that. Im not familiar with J Reds at all. Unfortunately in my area there are no dealers. I've seen one JRed in the last three years. Probably good for me or i would be addicted to them also. Tree Freak says a JRed 670 Champ is the same cylinder as the 268XP. I'll check that out. If it is and it's rated at 13,500 max no load, then I will consider my question answered. If not......? I may give up. There are no old Husky experts reading this? If so, please help. Again, thanks for all the input.
 
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