Compression for 350x

[Satsol67]

I look at the service manual and it shows it needs to be at 185lbs.

My question is what is the lowest before time for a new top end? It does smoke some its not like a bug sprayer or anything like that so I am wondering if it would be the oil ring for is it time for valve seals?? or even both.

Please advise.

Thanks,

Ron

[rally4x4racer]

the manual I use says 178 +/- 14 PSI (i think) - in that case the min would be 178- 14 or 164 --------------yours does not show a tolerance?

[NOS_350X]

I would remove your top end, mike it, buy rings and a top end gasket kit with valve seals included. Break your glaze on your jug and throw a fresh top end back togeather, Then you are good for another 20 years.

I personally would do the following mods:

higher compression piston
new valve springs
complete SuperTrapp exhaust
port and polish
14/40 gearing
new o-ring chain with case saver
rebuildable stainless steel oil filter
high performance air filter

misc apearence mods like low bars alloy and chrome bling to make is shine

These mods will give it a nice jump in power but still make it a very reliable machine, as long as you use the right octane for what ever compression you choose.

Ok, just new rings wont give you 20 years. How old these engines are getting its time for a whole new piston. and the reuseable oil filters SUCK they let crap through. The guy didnt ask what mods to do to his 350x so i dont see whyyou posted that. IMO your post was USELESS.

[Satsol67]

Being I'm going to pull the top end would it be best to go a head and split the cases to so I can look at the geas and crank?

[ceaserthethird]

unless their's a problem with the lower case area , i would stay way !

if your pretty good at fixing lower ends or over hauling motor's go right ahead !

[Satsol67]

Ok, just new rings wont give you 20 years. How old these engines are getting its time for a whole new piston. and the reuseable oil filters SUCK they let crap through. The guy didnt ask what mods to do to his 350x so i dont see whyyou posted that. IMO your post was USELESS.

I'm not sure if that was ment for me but as far as I can tell its all stock.

The reason I asked about pulling the cases apart is I want to be sure that the crank bearings and seals are in good shape along with all the other internals. Is it worth going 1 size over or just leave it stock bore. I know it wont give me anymore power I just dont want to do this twice.

As in rebuilding the lower and top end I sure I can do it. I have built many motors in my day but I just like to ask some questions just to be sure.

[Dirtcrasher]

I also wouldn't touch the bottom end unless the motor is real tired.

There are ALLOT of 21 year old 4 strokes out there that are on the original clutch and main bearings.

Truth be told, I can't think of one weak spot in the lower end of the 350X motor, seems incredibly bullet proof.

But the top end is another story. Although it is still bullet proof, a low oil level, old oil, dirty or improperly installed oil filter all seem to do in the head and cam of a 350X which aren't cheap to fix.

[Satsol67]

I also wouldn't touch the bottom end unless the motor is real tired.

There are ALLOT of 21 year old 4 strokes out there that are on the original clutch and main bearings.

Truth be told, I can't think of one weak spot in the lower end of the 350X motor, seems incredibly bullet proof.

But the top end is another story. Although it is still bullet proof, a low oil level, old oil, dirty or improperly installed oil filter all seem to do in the head and cam of a 350X which aren't cheap to fix.


Ok great then I wont get into the bottom end. There is one thing I have noticed about the kicker. There is a spot that seems like the gear is worn or something because it will skip that spot not really a big thing beause because it goes right by that spot.


So my question is do I have to split the case to fix this?

[Dirtcrasher]

Ok great then I wont get into the bottom end. There is one thing I have noticed about the kicker. There is a spot that seems like the gear is worn or something because it will skip that spot not really a big thing beause because it goes right by that spot.


So my question is do I have to split the case to fix this?

No, the kicker parts are under the clutch cover.

Most likely someone did some work in there and screwed up reassembling the kicker shaft and gears and damage has resulted. For some reason, lots of people have allot of trouble installing the kicker shaft and spring.

Anyhow, make sure you buy a manual BEFORE you tear it down and read the top end chapter. OR...... you'll end up screwing something up bad, ok bud?

[Satsol67]

I got the manual all ready so I will look into it more. I plan on replacing all the bolts with stainless ones so see then.

Thank,

Ron

[ceaserthethird]

Don't forget to post pictures as your tear that Motor up !

Good Luck