High speed problem
 

Bought a set of high speed gears for my M4. Problem now is I keep ripping the back off my pistons. Fires about a 100 rnds perfectly then it jams and the pistons first tooth is ripped off. This has happened to me twice now. Is there something I should do to that first tooth to prevent this ?

need a highspeed piston, half teeth and a few teeth are missing in some models.

This should work http://www.redwolfairsoft.com/redwol...l?prodID=22719

What spring are you using? It sounds like your sector gear's engaging the piston before it's back to battery.

I have the flat gears so I have to use a full tooth piston.

Mantelope, I'm using a Guarder SP90 spring.

What's in your gun? Piston? What's the RPS and FPS?

Ripping the back off the piston can be caused by many things: bad piston, sector gear coming forward before the piston returns home, angle of alignment being really off, etc.

Using Hurricane high speed gears, 1st piston was a King Arms and 2nd was an Area 1000. I haven't had it chrono'd or anything but i'm using a Guarder SP90 spring. I haven't gotten the Area 1000 piston out yet but it's doing the same thing as it did when I broke the King arms. The gears just continue to spin.

Try using a quality piston like a Prometheus or Super Core (haven't tried the Super Core myself, but everybody raves about it). I've also had decent results with Guarder and Modify. Make sure you trim at least the 2nd to last tooth like should always be done with a high speed setup.

If that doesn't work there's the option of short stroking the piston, and/or installing a larger spring so the piston slams home faster (ideally before the gears are ready to pull back the piston again).

You mean the 2nd from the spring end of the piston ? How much should I trim off ? Here is a pic of the King Arms piston

hey
 

Hey man:

THat's a pretty common problem with high speed setups. It means that there's a lotta resistance to your piston moving so that your piston moves down the cylinder too slowly and your gears complete the revoluation because your piston hits the cylinder head.

You can try to increased your mainspring.

Another thing is to make sure that your Hop Up works correctly (especially the rubber) as that caused me to wreck a lot of problems in the past.

What spring does everyone typically run in a high speed setup ? The first piston I broke I was using some old bb's and one got stuck where the hop up rubber is but I thought it happened b/c the bb wasn't a good one

Well, you always want to use good BB's to ensure a smooth operation, but as for a spring, I'm thinking something that might put it around 360 or so. You'll be putting A LOT of stress on your gun if you're using a high ROF/high FPS set up, you could do that if you want but the money to up keep it isn't worth it in MY opinion.

None of my 3 HS setups runs more than a SP100/M100. Usually a spring rated around 330-ish fps does it for me.

Why not short stroke your piston?

Uhh... no.

That's for helical gear sets. It has nothing to do with high speed gear sets, and if anything, you'll rip the teeth even faster.

DSFD506: Start by shaving off the 2nd tooth. It sounds like you're experiencing gear crashing. You can try going up to a Prometheus MS100SP or even as high as a Systema M100

Also, detail what motor you're using and exactly what battery you're powering it with (voltage, cell capacity and if possible, cell size.)

Yeah, remove the first tooth and shave 1/3rd to 1/2 of the second, piston will probly thank you.

I'd like to see how the sector gear would hook on to the piston if he does as you suggest by removing the first tooth. He'd essentially be manually creating the exact problem he's trying to avoid.

I'm using a 9.6v battery with the stock motor that came in the M4 originally. It was an AIM M4 with standard gears i'm guessing.