8 tooth sprocket and a extra driver

[regulate34]

ok so I went to the dealer today and picked up a 8 Tooth rim sprocket for my MS460. Wanted to see the difference for my self. The guy as the store said I would need to Add 1 driver to my chain to fit the 8 tooth. I didn't have the chain with me and didn't feel like buying another chain. He then said "if the chain is used and stretched it might fit".

Any way I got home and it fit. Went and cut a mountain of cookies. I haven't timed it but I know its faster in 16" wood.

So now to my question.

When I get a new chain with I have to get it with a extra driver?

 

[lambs]

If the dealer is a Stihl dealer, he might just know what he's talking about.

Someone will know the definitive answer to this, but my guess, and that's all it is, is that it might work without the extra DL but it could give you a fit putting it on. You'd likely back off the tensioner almost all the way, then try it. Keep in mind Stihl chains do not stretch a lot either. You could buy the standard DL chain, try it, and if it will no way go on, get the dealer to add a DL to it on the spot.

My late Dad's 066 is a bear to get a chain on, and it does not have the larger sprocket on it either. I think it takes 91 DL and really could use another link.

 

[mdavlee]

Most of the time you won't need the extra drive link.

 

[redfin]

I have an 8 pin for my 660 on 25" bar plenty of room. I have put a new Rs chain on with no issue.

 

[blsnelling]

I haven't timed it but I know its faster in 16" wood.

Put it on a stop watch. You might be surprised. IMHO, it takes a very strong 90cc saw to make a 8-pin rim worth while.

 

[mountainlake]

Yes put a stop watch to it, none of this it feels faster and make sure to load the 7 pin. Steve

 

[jeepyfz450]

I trim the tail of the bar. I have run 7,8,9 and 10 pins with the same bar and chain

 

[R/C Pilot]

I run an 8 pin rim on my 460 with a 25" bar. A new chain is a bit tight to get on but will go. I like the 8 over the 7.

 

[Old Sam]

Put it on a stop watch. You might be surprised. IMHO, it takes a very strong 90cc saw to make a 8-pin rim worth while.

My MS660 is running a 8-pin with a 32" full house and it's crazy...I want to get it beside my buddies 395xp in some big wood; he runs a 7-pin 24" and cuts firewood for a living.

 

[sawfun]

My 066 and 064 liked an 8 pin about as well as the 7 pin but my 7 pin 395 would smoke that 066 and 064 and both saws were stock running 36" bars. The Stihl having a dual.port cover.

 

[Mastermind]

No need for an extra driver that I've seen......

 

[regulate34]

Ok tommrow afternoon I will work on getting a video set up.

 

[Big_Wood]

as long as you have 7.5 drive links showing off the end of the bar tail your good to go with a 7 or 8.

 

[AKDoug]

My ported 441CM, which is most likely every bit as powerful as a mm'd 460, is definitely slower with an 8 pin than a 7 with a 20" bar. A 24" bar would just make it worse.

 

[Terry Syd]

My Chinese 365BB runs an 8-pin and 24" bar in Ozzie hardwood. Even loading it on the spikes with the bar buried it has no problem - but then again, I re-jetted the carb to be able to do just that.

I had to trim the tail of the 20" bar to run a 9-pin on the 029. If I wear out these chains, I'll get a couple of extra DLs added to the next set of chains. Taking the circlip off every time I need to change a chain is a pain.

 

[TBrown]

I used to help a guy who logged. He ran 20" bar on the 460's most of the time. He would buy 71 DL loops for Stihl bars. They would fit with a 7 pin but not with a 8 pin. He did this to account for the stretch over the life of the chain. Cutting in the landing is hard on chains. He ran classic Stihl chisel.

 

[RyanTowry_81]

My Chinese 365BB runs an 8-pin and 24" bar in Ozzie hardwood. Even loading it on the spikes with the bar buried it has no problem - but then again, I re-jetted the carb to be able to do just that.

I had to trim the tail of the 20" bar to run a 9-pin on the 029. If I wear out these chains, I'll get a couple of extra DLs added to the next set of chains. Taking the circlip off every time I need to change a chain is a pain.

any video of said 365BB with 8 pin and 24" bar in hardwood?

 

[Terry Syd]

I don't have a video, but AUSSIE1 has some videos of his Chinese 365BB working out. He had one with a 28" bar I believe in a big piece of wood, the engine was screaming. That was with the early BB kit and it required a fair bit of cleaning up to be workable. The later kits are close enough that you don't have to rework the transfers, just clean up the wonky exhaust port and extend the intake timing a bit. Here's a thread - http://www.arboristsite.com/community/threads/out-cutting-firewood-with-the-365bb-and-385xp.141746/

As far as the carb mods for more torque, we've been discussing them in this thread, see post #66 - http://www.arboristsite.com/community/threads/dolmar-7900-carb-upgrade.229528/page-4

 

[RyanTowry_81]

I don't have a video, but AUSSIE1 has some videos of his Chinese 365BB working out. He had one with a 28" bar I believe in a big piece of wood, the engine was screaming. That was with the early BB kit and it required a fair bit of cleaning up to be workable. The later kits are close enough that you don't have to rework the transfers, just clean up the wonky exhaust port and extend the intake timing a bit. Here's a thread - http://www.arboristsite.com/community/threads/out-cutting-firewood-with-the-365bb-and-385xp.141746/

As far as the carb mods for more torque, we've been discussing them in this thread, see post #66 - http://www.arboristsite.com/community/threads/dolmar-7900-carb-upgrade.229528/page-4

Thanks for the info, I have a 365 project and every little nugget helps.

Sorry for the hijack.

 

[Terry Syd]

The BB jug also needs a bit of work down low in the transfers in order to take advantage of the 77ccs. Both Neil (chainsaw racer) and I move the side of the cylinder up to the level of the gasket. I also trim under the piston skirt and put a couple of small holes in the side of the piston that protrudes below the cylinder. All that work is just to make sure that the transfers don't get short-changed at BDC.

I definitely suggest modding the Zama carb as indicated in the 7900 carb thread. The increase in torque has to be experienced in order to believe it. Do the mods, that 365 of yours is gonna surprise you!