spudulike

You would be barking if you purchased the MS290, the 365 is a solid workhorse that will carry on for years, it is a pro saw that will carry a 20" for ringing up all day and the bottom end is used on the 372 so is rock solid. The MS290 is a smaller version of the MS390 and is predominantly plastic and hard to work on! Buy the 365

The mufflers on chainsaws are just small cans that try not ot restrict flow but do try to restrict noise. They use a mix of small outlet holes and baffle plates - all this restricts the flow of gasses through the engine. A muffler mod is just a very basic way of improving this flow whilst trying to not make a saw damn well deafening:blushing: Teh TZ you talk about will have had an expension pipe, this is a way of varying the power curve and torque of an engine with its exhaust. The science of the expension is exactly that, it is dependant on the engine and is then designed with a specific outlet length and diameter, length and diameter of the expansion chamber and same on the outlet pipe. The expansion allows the shock wave of the engine exhaust to bounce back on the outer wall of the expansion and bounce back in to the engine, charging it with a slight mix of exhaust and unburnt fuel/air vapour....more charge = more power:thumbup: Don't get mixed up between our compact mufflers and the racing TZs of the 1980s. On a separate note - I saw a tripple engined drag bike once based on three TZ750s - that was nine expansion pipes and sounded.....pretty damn weird:thumbup: Has anyone tried revving two saws together at the same time in unison....try it:thumbup: Pro Am 1980s starting grid comes to mind!

Another busy weekend, MS200T, big airleak, tracked it back to a broken lug and hole worn in the side of the crankcase. Degreased it and filled it with JB weld, replaced seals and impulse line, loads of holes stripped of their threads, two punctured holes in the oil tank where overly long bolts had been used. Cut small bits of thread with a cut out and screwwed them in with loctite and fitted shorter bolts - oil tank now sealed and 100% pressure and vacuum tested. 254XP in for porting - spent late afternoon blowing bubbles at me so fitted a new seal an all good with the airleak it had:lol: This seal would have gone in time and probably seized the engine - I guess it is why I get so busy on repairs - jobs done right and right first time:thumbup:

I can give it a go, I would need to check out the piston as these older Stihls can have a fair bit of slap on them and that won't be a good starting point but should be able to get more out of it - nice conventional design:thumbup:

Blimey Dave, where are you finding them - yes, without doubt:thumbup:

not driven the bar studs out but would reckon they should be knocked through to the oil tank and the holes and inner tank should be degreased than the bolts put back in with a bit of epoxy around them to seal them in - put the bar back on with the epoxy still soft and do it up to avoid them shifting later. Thats my suggestion without doing the job before - more used to screw in ones.

Not done one yet but have consulted my files and it is a strato saw - never a great sign as it cuts a lot of flow from the inlet manifold - simplest thing to do is a muffler mod and will reap the easiest gains for the least work!

Anything bar a decent going over would have been a bad call on a four month old machine. Hopefully I can get years of future service out of it:thumbup:

Bit of a bummer, I feel for you:thumbdown:

I take it the chain is sharp and the fuel mix is fresh - I would normally take the exhaust off and look at the piston for scoring and then strip and clean the carb - worth also checking the fuel tank breather is clear of dust.

Vinyl are about the best, they don't disintegrate like the others!

I've put my glasses on, I think I have noticed the slight difference:thumbup:

Is that muffler standard:001_rolleyes:

Yes:thumbup:

I think I saw a rabbit crawl out of that hole:lol: Nice one!

And don't get hung up on that cylinder base on the first pic left hand side, it is a clam style engine where the base of the cylinder forms the upper part of the crankcase. Closed transfers are generally found on more expensive Pro saws and open on semi pro/homeowner saws, there are many exceptions to this, the MS200 being one of them. As Wes says, closed ports generally have better flow and velocity plus a rounder top to the transfer is far better than the angular affairs usually found.

Man.....18,000rpm, thought my saws were fast revving:lol: It is the oil that dictates the mix and not the saw. Most decent quality oils nowerdays mix at 50:1, there are a few exeptions such as Amsoil at 100:1. The 25:1 comes from the 1960s - 1980s where the oil was a bit under developed. Run a modern machine on this and it will smoke like beggary and carbon up. Use decent quality oil and mix to the OILS instructions

Yeah - you probably purchased an oil cap for the fuel tank or vice versa:lol: I have noticed that the caps can become tight and then it gets so when you try to flip the cap down, it is out of position...bloody annoying IMO and easy to get the fuel spilling out Grrrrrr

TBH I run a tad more than 50:1, it is just my choice, the theory you are talking about is that the more oil you have, the less fuel there is in the mix so you are in fact leaning the saw down by adding more oil, there is some logic there but if you tach the saw to run the rpms it should......... My take is that if you add a little more and then ensure your saw is set up correctly on the carb, then you shouldn't get issues and I have had none but I actually do very little cutting as all mine is for the log burner. I have had one or two saws in that have expired for no particular reason but the main cause of failure has been air leaks, bad fuel or incorrectly adjusted carbs. The "No reason" ones were probably dodgy pump fuel or just damn big bars and a tad to little oil but can't substantiate this. I do get saws motoring - I have seen the 357XP hit 15,000rpm, the 346XP do the same and 372XPs up to 14,500 - all ported but running on Stihl HP IMO, if you mix bang on 50:1 and cock up a little then you may have issues. if I cock up a little using 45:1, I am back on 50:1 I like the new Sugihara marketing, thought I had a virus when that banner came up!!!

Step away from the dremmel:001_rolleyes:

A Komatsu powered Allen, the trimmer was an Echo and the blower a BG85:thumbup: Just can't help myself:blushing:

MS441 has a weird ring end running up the side of the exhaust port - not much you can do about it. The strato design really limits the amount you can take off the inlet port on most of these saws,

Yup, and a hedge trimmer and blower:blushing:

Yup, Barrie is a top dude:thumbup:

Sorry bud, no need to throw the toys out of the basket:blushing: Blimey, won't mention it again:thumbdown: