Wide Crank Tightening...

Discussion in 'Bicycle Repair' started by PhoobarID, May 10, 2010.

  1. PhoobarID

    PhoobarID Member

    Used to have the 4-stroke engine...so put on the 3 piece wide crank on the bike. Putting a 66 cc engine...didn't bother changing out this crank. Keep having the left side nut (the one with straight edges on each side and round on the rest of the nut) come loose. Have tried to tighten this with some channel lock pliers...but still comes loose because I can't get the jaws into the groove. Is there a tool I can buy or can use to get this tight? Would I be able to use red locktite to keep it tight?

  2. MikeJ

    MikeJ Member

    If it is the nut (I'm thinking it is a bolt), what my experience is: I had to use a 14 mm thin wall socket to tighten it. I don't recommend red locktite. Blue or green locktite allows removal in the future. With red locktite, you will need an open flame torch to heat the nut to soften the locktite for removal. Maybe borrow a range of sockets and the handle from a buddy.
  3. Ghost0

    Ghost0 Guest

    Did you have to use bottom bracket adapters for the spindle? If so you may have installed them backwards. For cup and cone bearing sets the one piece cup, the one I think you describe, should go on the right. The other cup that has the locking ring should go on the left. If you are not using the adapter to go from the 1 piece to 3 piece then disregard as with just the threads in the frame you could not install the cups on the wrong side.
  4. PhoobarID

    PhoobarID Member

    It's a lot more bigger than anything I have in my toolbox...even the 21 mm socket I have.

    The more I think about it...not sure if red locktite would even hold on the plastic threads.
  5. PhoobarID

    PhoobarID Member

    Here's the setup I have in the attachment. The one I'm talking about it the left handed one (as you're looking at it) that is flat on the top/bottom of this nut. That one is mounted on the motor drive chain side. If I remembered right...they would only install one way...so I couldn't get them backwards.

    Seems like there's a tool available for this...but can't remember the name of it or I'd get it.

    Attached Files:

  6. MotoMagz

    MotoMagz Member


  7. Ghost0

    Ghost0 Guest

    OK it sounds like you installed the adapters backwards so the thread direction is not keeping the cups tight. There are two cups, one has a lock ring. The lock ring and corresponding cup should go on the left side of the bike. The one piece cup should go on the right.
  8. PhoobarID

    PhoobarID Member

    Yep...that's what's happened. Since the package came without any directions & there were none on the vendor's website...did the best I can do. Since I won't have time till Saturday after I mow the yard...that's the 1st thing I'm going to get apart. Gotta another gallon of gas on the way home from class & will get it mixed & ready to go.
  9. PhoobarID

    PhoobarID Member

    Before I forget...does it matter what way the two plastic ends are installed?
  10. PhoobarID

    PhoobarID Member

    Just changed out the 3 piece bottom bracket today. If you ordered one of these kits with no directions (like what happened to me)...here's how you do it:

    1. Unscrew the crank which came with your bike.
    2. Taking a large screwdriver & a hammer...you're going to knock out each cup on each side of the bike after taking out the bearings.
    3. On the left cup (which is the one where you feed through the bolts. The right side is the one which you screw the bolts into)...you feed through the three allen-head bolts after putting on the cup which allows you to feed through the bolts...but not tighten them down. The will allow you to put the tightening ring on that side as well.
    4. Taking a piece of wood...place it flat on the new cup & gently tap the left side cup into place. Should be flush to the bottom bracket.
    5. Put in the three screws making sure they reach out the other side of the bottom bracket.
    6. Taking the other cup...match up the holes with the screws you fed in from the other side.
    7. Going to the other side...hand tighten each of the three bolts to make sure you match up without cross-threading to the right side of the bottom bracket.
    8. Tighten these three bolts with an allen-head wrench till the cups are flush with the bottom bracket.
    9. Take the clear plastic tube & feed it between the two sides between the cups.
    10. Taking your bearings...put the rounded side into the cup of each side you will be tightening down with some lithium grease.
    11. Feed your crank through from the right side. Don't connect the sprocket yet.
    12. Remember that each side will only turn one way. The left side gets the locking ring...while the right side gets the one with flat sides on the top/bottom.
    13. Hand tighten till you get them screwed in...then use your wrench to tighten down. The shaft will tighten as you tighten each side.
    14. When each side is tightened down...grab your sprocket...10mm holding bolt & the nut.
    15. Line up the notch on the right side for the sprocket. Put in your 10mm bolt & gently tap it down on the flat head...making sure your flat side of the bolt is against the notch in the shaft. Tighten down your 10mm nut/washer till tight & not being able to turn the sprocket. (NOTE: You can get this spot welded.)
    16. Attach each side arm for your pedals. Tighten down each 14mm bolt to hold on each arm.
    17. Attach your pedals. (NOTE: If you have stock OEM pedals...they will be too small to work with these arms. You can get some nice pedals. Mine are black magnesium Iron Crosses I got on closeout at a bike shop.)

    Hope this saves you many of the headaches I went through by the vendor not putting directions with the parts or on their website.

    Since the bearings tore up as soon as I took them out to change out the sides...I will be buying more tomorrow at the bike store in town.

    NOTE: Wanted to add...one way to tighten up the right side (the one on the bike sprocket)...is with a 10" adjustable wrench. Was able to tighten down the left side (lock ring side) with the jaws on the adjustable wrench all the way out. Will by buying a bottom bracket wrench this weekend when I get my paychecks. Till then...it will hold.
    Last edited: May 17, 2010