Building a 390XP Monster

[Trx250r180]

Yes, it's wearing a pair of 34PJs and T5 Toomeys

try the 35 mm air strykers ,you will be shocked on throttle response difference

 

[blsnelling]

try the 35 mm air strykers ,you will be shocked on throttle response difference

I don't think they were using those back when I had mine. I had a Duncan Racing National Midrange port job. It also had Cool Design heads and intake. I ran a couple degrees of timing advance with a lightened flywheel. A stock Banshee was rather boring

 

[Trx250r180]

I don't think they were using those back when I had mine. I had a Duncan Racing National Midrange port job. It also had Cool Design heads and intake. I ran a couple degrees of timing advance with a lightened flywheel. A stock Banshee was rather boring

loren and lenny duncan build some good 2 running 2 strokes ,the banshees are still real popular in the sand dunes around here ,arlen at lrd used to do my engines

 

[ChainsawmanXX]

[video=youtube_share;3vT4DeVoyd0]http://youtu.be/3vT4DeVoyd0[/video]

Whats up with cutting up that perfectly good grade log??


:jester:

 

[blsnelling]

Those of you at the GTG know that I seized the piston in this saw first thing Saturday morning. It turns out that the ears on the bottom of the cylinder were too long and pinched the piston when bolted down. It only got tight once hot, so couldn't be felt on the bench. The cylinders fine. All it needs is a new piston.

I've been toying around with the idea off making this saw a GTG toy. I'm talking more aggressive porting and a pipe. I might even go with a two-piece head. I want another cylinder to do that with though. Anyone have a spare 390XP cylinder laying around that they'd part with?

 

[Mastermind]

Those of you at the GTG know that I seized the piston in this saw first thing Saturday morning. It turns out that the ears on the bottom of the cylinder were too long and pinched the piston when bolted down. It only got tight once hot, so couldn't be felt on the bench. The cylinders fine. All it needs is a new piston.

I've been toying around with the idea off making this saw a GTG toy. I'm talking more aggressive porting and a pipe. I might even go with a two-piece head. I want another cylinder to do that with though. Anyone have a spare 390XP cylinder laying around that they'd part with?

Those pipe saws do tug on a fellers "I wanta" pretty hard don't they Brad?????

 

[blsnelling]

Those pipe saws do tug on a fellers "I wanta" pretty hard don't they Brad?????

Yes they do, especially when you have a first class craftsman willing to build you a pipe!

 

[Mastermind]

Yes they do, especially when you have a first class craftsman willing to build you a pipe!

I've got one hanging on the wall............ :msp_wink:

 

[Stumpys Customs]

Those pipe saws do tug on a fellers "I wanta" pretty hard don't they Brad?????

Yes, yes they do.

 

[Mastermind]

Yes, yes they do.

It was great meeting you this weekend Stumpy.

 

[blsnelling]

I've got one hanging on the wall............ :msp_wink:

For a 390XP?

 

[Mastermind]

For a 390XP?

I had Frank build me one for my 066.

I had planned to run it at the GTG on the BB 064 I built but it didn't get done in time for me to tune it in. Frank gave it to me Friday afternoon at the GTG. I did make a few cuts with it but the port timing wasn't high enough for the saw to start working the pipe........I'll fix that though.

 

[HEAVY FUEL]

We started talking on the way home that was a good thing you didn't send the saw to scotts for the 390 build off. If that happened when we had it would not have fun. Glad you ya found the problem & its an easy fix.

 

[Stumpys Customs]

It was great meeting you this weekend Stumpy.

Likewise buddy, I shoulda asked to put that pipe on the 066 I brought. It's running some very high durations. That cyl may get set on a shelf to use for a pipe saws some day. I've got another virgin cyl to play with for it.
Now If I could just figure out these rumors of running low durations & still making rpms. I've got's lots to learn yet & seems that I'm always a step behind everybody else:msp_wink::bang:

 

[blsnelling]

We started talking on the way home that was a good thing you didn't send the saw to scotts for to 390 build off. If that happened when we had it would not have fun. Glad you ya found the problem & its an easy fix.

Wow! That wouldn't have been a fun situation at all! Yikes!

 

[HEAVY FUEL]

Here is Paul's 390 run by terry, not sure what times were.

[video=youtube;u6TpzdTW9OU]https://www.youtube.com/watch?v=u6TpzdTW9OU&feature=youtube_gdata_player[/video]

 

[blsnelling]

Looks like a 24.xx to me. Sweet. If I hadn't grown up with Stihls, I'd be a Husky kind of guy.

 

[Jacob J.]

Those of you at the GTG know that I seized the piston in this saw first thing Saturday morning. It turns out that the ears on the bottom of the cylinder were too long and pinched the piston when bolted down. It only got tight once hot, so couldn't be felt on the bench. The cylinders fine. All it needs is a new piston.

Are you referring to the flange on the bottom of the cylinder that extends down into the case? Did you have the base turned without
taking material off the flange?

 

[AZLOGGER]

The chain is about to stop and the engine's still revving. It's to the point of slipping.

Brad:
I don't know if this is the problem, but worthwhile to check it out. That same clutch is used on the 395's, so it should't be slipping.
Just my 2 cents worth! :msp_thumbup:

 

[FATGUY]

Are you referring to the flange on the bottom of the cylinder that extends down into the case? Did you have the base turned without
taking material off the flange?

I thought I had taken the same amount off of the flange as I did the base, I either did not, or didn't account for the loss of the base gasket. I don't know how many of these I've done by taking the same amount off both surfaces and have never had this problem.