Thinking about having a machinist make me a cylinder tube

Discussion in '2-Stroke Engines' started by plinko, May 23, 2010.

  1. plinko

    plinko Member

    I thought about having a machinist make me a custom cylinder tube with an Iron lined cylinder wall for a grubee80/66cc gt5.Any Ideas on this or Is this a waste of time?

  2. GearNut

    GearNut Active Member

    There are companies that do this, L.A. Sleeve comes to mind.
    I doubt that they would do a HT engine though, but ya' never know.....
    The stock cylinder will need to be machined to accept the cast iron liner with the liner having an overlapping lip on the top to enable the cylinder head to lock it into place.
    Also, the cylinder ports will need to be machined in place before the liner is pressed in.
    It is quite a daunting task to try to do in your garage!
    I have had 4-stroke cylinders lined, and have worked on 2-stroke engines that were lined previously. It is a great alternative for older engines or antique engines when finding a good cylinder is impossible or cost prohibitive.
  3. plinko

    plinko Member

    Would this last longer than the chrome plated job?I am looking for reliability and longer life which Is why I have thought of this.I know a machinist who can make this stuff and helped design briggs and stratton lawnmowers In the 60's.
  4. Is there a particular material that works best for this? I know the old Volvo and Benz autos used a high nickel content cast iron that gave them the potential of 300,000 plus miles with little wear.
  5. GearNut

    GearNut Active Member

    plinko: A chrome bore can easily outlast a cast iron bore, but a cast iron bore has the advantage of being re-sized to accommodate a larger piston for the sake of rebuild ability.
    Even a chrome bore can be striped and re-plated. Though, once again, it is a matter of cost versus practicality. If a new cylinder can be had for cheaper that a re-plate, why do it?

    Jack: I am by no means anywhere near an expert on proper cylinder alloy. I do know however that having a high nickle content would lead towards having a lubricity benefit. Not necessarily making it resist wear through toughness but rather through slickness. (is that a word?)
  6. plinko

    plinko Member

    Just worried In a few years these ht engines will have no parts available due to the epa ban and future laws Involving making 2 strokers Illegal and Figured having one made of Iron would last longer.I see now I was wrong.Think I will still have an Iron lined cylinder made So I can do rebuilds though.And stock up on 2 or 3 chrome cylinders for when the hard times kick In.
  7. GearNut

    GearNut Active Member

    Some of the 50cc engines do have a cast iron liner in the cylinder.
    I agree with you 100% on stocking up extra parts.
    One thing to consider though, the bearings used in these engines as from the factory are pretty much junk. If you want to make an engine last and last, you need to tear the engine down to the itty bittys and install quality bearings through out.
    Stock up on pistons, piston rings, cylinders, heads, a spare crank or 2, CDI units, primary ignition coils (called mags around here), clutches and matching clutch friction pads (there are round ones and square-ish ones) and gasket kits or make up your own gaskets as you go along.
    The best bet would be to buy a bunch of kits and set them on a shelf somewhere. As parts break and wear out, you can mix-n-match parts out of the kits to keep things going. Just be sure to only buy one type of kit from one vendor and get them all at once, as the kits will vary from the same vendor depending on exactly what they get shipped from china. The factories do the switcharoo thing a lot!
  8. darwin

    darwin Well-Known Member

    Machine shops arent cheap, the few I've been to had like a 300$ or so minimum just to setup a machine. Then theres the design aspect plus material costs. I think I'd buy 2/3/4 ht motors and let that be it. Should last you for 20 years or so lol.
  9. Fabian

    Fabian Well-Known Member

    Have to agree with GearNut plinko: plinko: A chrome bore can easily outlast a cast iron bore

    Why would you want to use two materials with differential expansion properties for the piston and cylinder.
    Aluminium expands at twice the rate of cast iron, so with a cast iron bore you need larger piston to wall clearances and aluminium is more responsive to changes in heat variation, helping to maintain more consistant piston to bore tolerances.

    Last edited: May 26, 2010
  10. plinko

    plinko Member

    I don't know fabian.After seeing that Most machine shops have a 300 min deposit not counting labor.I am just gonna stock up on parts and let It go till I can save up and get a morini and not have to worry about Issues these h.t. motors seem plagued with.Maybe my grubee gt5 will be a lil more reliable.
  11. plinko

    plinko Member

    You got a point.Think I'll take your advice and save up for spare parts and a morini.
  12. anthony1973

    anthony1973 New Member

    Dang If you do and Dang If you don't even morini's break down eventually.Just accept the fact that nothing last forever and buy spare engines.Same with the automobile world.Eventually It'll tear up.My suggestion Is If you do a cheap ht go with grubee from a reputable vendor with a good warranty plan and parts on hand to do rebuilds.Morini's are not cheap anc can be hard to get parts for at times and although more reliable.Still gonna break down.Gotta accept facts that eventually It'll tear up If you run It alot.