What to expect from 7900 swap

[FELLNORTH]

I DONT MEEN TO HIJACK YOUR THREAD, BUT DOES ANY ONE HAVE ANY INFO ON THE BAILEYS BB KIT?
IS THIS A QUALITY ALTERNATIVE?
OR THE OEM STUFF OUT PERFORM IT?
THANX:monkey:

 

[davefr]

I DONT MEEN TO HIJACK YOUR THREAD, BUT DOES ANY ONE HAVE ANY INFO ON THE BAILEYS BB KIT?
IS THIS A QUALITY ALTERNATIVE?
OR THE OEM STUFF OUT PERFORM IT?
THANX:monkey:

The BB kits have a tainted reputation so I'd say they aren't a "quality" alternative. I even question whether they outperform OEM. There are other higher quality aftermarket suppliers out there.

It seems like the designer's of these kits was guessing as to how to ensure usable performance. At the same time the quality control engineers were a "no show".

 

[4mocajuns]

OK so it's on its way...... anything I need to know? Special tools, tricks of the trade, what out for that thingy falling out....... those kinds of things.:jester:

 

[rms61moparman]

OK so it's on its way...... anything I need to know? Special tools, tricks of the trade, what out for that thingy falling out....... those kinds of things.:jester:

Yes sir,

This right here is the best piece of advice I can give you.......

Before you start to install the piston make the room as close to TOTAL SILENCE as possible!!

No air compressor, no radio, no MP3, no kids, and if you aren't alone, stress to the others who are with you that you MUST have total silence..........






That way when the little circlip goes zinging across the room, you will be better able to hear where it lands!!!!!

Don't ask how I know this............It ain't as funny as it seems right now! LOL

Mike

 

[Fl_Airboater]

The BB kits have a tainted reputation so I'd say they aren't a "quality" alternative. I even question whether they outperform OEM. There are other higher quality aftermarket suppliers out there.

It seems like the designer's of these kits was guessing as to how to ensure usable performance. At the same time the quality control engineers were a "no show".

I ordered a BB kit from Bailey's (name on list, backordered). The more I thought about it I decided to get an OEM 7900 P&C, My thinking is that I know I am getting a high quality Mahle piston and cylinder with the OEM kit, if I go with the BB kit I don't know what kind of quality I would be getting. I canceled the Bailey's BB kit order and got the oem 7900 kit instead. I can now say without a doubt that I am confident in what I have now.

 

[davefr]

Yes sir,

This right here is the best piece of advice I can give you.......

Before you start to install the piston make the room as close to TOTAL SILENCE as possible!!

No air compressor, no radio, no MP3, no kids, and if you aren't alone, stress to the others who are with you that you MUST have total silence..........






That way when the little circlip goes zinging across the room, you will be better able to hear where it lands!!!!!

Don't ask how I know this............It ain't as funny as it seems right now! LOL

Mike

Yes, that little circlip always hates to be given a new home in the piston and tends to retaliate. When it goes flying it always tries to go to the most obscure corner of your shop where you're least likely to find it.

You need to beat it at it's own game. Take a clear plastic bag and throw it over the piston and work the circlip in from outside the bag. Make sure you seal off the crankcase hole with rags because that's it's second favorite destination.

 

[K9-Handler]

OK so it's on its way...... anything I need to know? Special tools, tricks of the trade, what out for that thingy falling out....... those kinds of things.:jester:

Well, the circlip subject has been covered -- except I think I had a harder time getting them out than in.

You will need a ring compressor. I made mine out of a 1/2"-wide piece of 2" schedule 40 PVC pipe with a 1/2" wide slot cut out of the side to get it out from around the connecting rod when you are done. I've never had a ring go in easier! I think the plastic gave it just enough slipperiness.
You also need something to hold the bottom of the piston up (and flat) while you are sliding the cylinder down onto it, so the crank just doesn't turn from the downward pressure. I made one out of a piece of 1/2" plywood, two inches wide and about 4" long, with a slot milled about half-way down the center to, again, clear the connecting rod. That worked like a champ, too.

Once the piston is installed on the rod most of your work is over. I remember feeling "Is that all there is? Can I be done already?"

 

[ericjeeper]

If the circlip does not go flying

And you can not find it after the saw is totally assembled.. When you realize the saw is locked up... Odds are the circlip is stuck to the flywheel magnet.. OR so I have heard. LOL

 

[4mocajuns]

Soon....... so soon. Damn USPS tracking software.:bang:

 

[husky455rancher]

I read about the great 7900 and had to have one. I bought a 6401 and put a 7900 kit in it expecting something better than a 79cc saw had. Seem to be about equal to a 372 but not as fast as an old 281. After i tested it and made sure it was running right i sold it.

ive ran a virtually new 372 and 7900 side by side. the 372 had a 20: on her and the dolmar had a 28" on it. i can honestly say the dolmar gave the husky a woopin. i dont like to knock the legandary 372 either but the truth is the truth.

 

[4mocajuns]

ive ran a virtually new 372 and 7900 side by side. the 372 had a 20: on her and the dolmar had a 28" on it. i can honestly say the dolmar gave the husky a woopin. i dont like to knock the legandary 372 either but the truth is the truth.

This is what I am wanting to hear cuz I have ran the Jonsered 2172(I think) and the 460 and really liked the way both of them cut. I also run an 066 from time to time and that power is intoxicating. I just hope the 7900 leaves me smiling.

 

[Fl_Airboater]

I did the swap on my 6401 and I can tell you the saw runs very strong now, it was powerful before but it is like a night and day difference between the 64cc saw and the 79cc one. I don't regret it one bit.

 

[clintb]

ive ran a virtually new 372 and 7900 side by side. the 372 had a 20: on her and the dolmar had a 28" on it. i can honestly say the dolmar gave the husky a woopin. i dont like to knock the legandary 372 either but the truth is the truth.

How about the 385 does the dolmar have more power than it?

 

[husky455rancher]

i dunno i havent done any side by side comaparisons. but i would have to say no the 385 is a pretty mean saw.

 

[Swamp Yankee]

ive ran a virtually new 372 and 7900 side by side. the 372 had a 20: on her and the dolmar had a 28" on it. i can honestly say the dolmar gave the husky a woopin. i dont like to knock the legandary 372 either but the truth is the truth.

Yup

Take Care

 

[4mocajuns]

OK so I got her put together this afternoon (f--in circlips) and I wanted to see what kinda compression it had so I gave it a quick snap and it fired right up! Ran it through a few heat cycles and then put it to the wood and :jawdrop::greenchainsaw:. Even once the flat top chain got dull it would still pull it! She wears a 24 inch bar for now but when Bailys has a good deal on a 28 or longer I will get one of those.

 

[Fl_Airboater]

Here's my converted 7900 with a 24" bar:

 

[4mocajuns]

Here's my converted 7900 with a 24" bar:

Did you mod the airbox cover and or muffler on yours?

 

[Fl_Airboater]

Did you mod the airbox cover and or muffler on yours?

Yes, I drilled some more holes in the cover. Don't know if they actually help the saw any, but they are there. I opened the muffler, took the "baffle basket" out and cut about half of it off and put the rest back in and drilled a hole in the front cover, inserted a piece of 1/2" conduit about 2" long and welded it. Put the 2 halves back together and welded it all up.

 

[mini14]

its worth it