What EVERY NOOB needs to read.


Active Member
Aug 13, 2009
Welcome NOOBS...I was one myself, been here done that..let's see if I look in my closet I may find a "T" shirt. Have learned the hard way...experience...before joining any forums.

These are the things that I do, I see that others such as the seals (which I've never had one go bad) mentioned. All these mods or replacements are most likely less then $50.00. Choose what works for you, ignore the rest, but here you have them.

1. Unpack engine, familiarize your self with them.
2. Check for any missing parts. Depending who you buy from you maybe out of luck. Two sellers come to mind. Luckyearlybird and BGF.
3. Remove head
4. Mill head (flat glass and 230 (or finer) grit sand paper. Rub gasket surface to insure it is flat. Check the cylinder also. This will ensure that you have a good gasket surface. Eliminates blown head gaskets by a large percentage.
5. Tap cylinder stud holes to insure they are taped to the bottom. Some engines aren’t taped to the bottom. This can be a problem with the studs pulling out..
6. Discard all studs and nuts. Studs the length of the cylinder are hard to find. Fastener supply has metric all thread. There are a number of vendors that have kits, including myself. But replace them.
7. Replace studs with Metric 8.8 (US Grade 5) Replace nuts with locking nuts. 8mm studs are either 1.0 or 1.25 thread, 6mm studs are 1.0 thread. 8mmX1.0 is not common, but I have 1 engine with them. Do this because the Chinese hardware is junk and prone to strip or shear off.
8. Replace spark plug with a NGK or any good brand.
9. Replace spark plug wire and boot (check with lawnmower supply) or rob from old lawnmower. Use wire core lead. The stock is junk and WILL cause problems down the road.
10. Mount the engine properly, no gaps between the bike tubes and engine mounts.
http://s982.photobucket.com/albums/ae309/Ron-Becker/Engine Mounting/ This will also help to keep the studs from snapping off.
11. Torque 8mm to 120 to 175 INCH POUNDS (max for cast aluminum is 204 inch pounds).
12. Torque 6mm to 60-70 INCH POUNDS (max on these are 75 inch pounds).
13. I install cylinder studs with lock tite, and let set overnight. Optional, I do it to all my builds.
14. I coat the head gasket with Copper Kote (I coat each side twice and let dry)
15. May need to bend exhaust pipe for crank or frame clearance. Recommend using heat. There are other methods, but you won’t hear that from me.
16. Remove or cap magneto white wire off. This is used for low watt lights…it won’t work with a light you can see with, believe me.
17. Re solder blue wire on magneto. Factory has had bad connections, (cold solder joints).
18. Wiring. BLACK Coil wire to BLACK CDI wire, BLUE coil wire to BLUE CDI wire.
19. When hooking the kill switch, don’t be concerned with wire colors. Hook one wire to the black wires, and the other wire to the blue wires. (See # 21)
20. Make sure all wires have a good connection (solder best) and use tape or better yet heat shrink.
21. Hook up kill switch wires AFTER you get engine running. This will eliminate a defective switch should you have trouble starting the engine.
22. Try not to drill holes in the bike frame. Weakens the frame, I did one and the frame split in two.
23. Do away with the clutch cable routing; there are a number of options.
http://s982.photobucket.com/albums/ae309/Ron-Becker/Homemade Mods/
24. On my kit the rag joint had gauge (Metric) 8.8 bolts, If not replace them. I replaced the nuts with lock nuts.
25. I sealed the wires coming from the magneto out of the engine with RTV.
26. Place a “O” ring in the carburetor throat. NAPA has an assortment. Buy them each.
27. Some say replace the axle with a better one. Never had an axle bend on me.
28. Use thin wire (I use Stainless safety wire).and wrap around the idle screw and secure to the carburetor.
http://s982.photobucket.com/albums/ae309/Ron-Becker/Homemade Mods/
29. For coaster brakes…Some say trim the cap, but I don't like it.
‪Bearing cap mod‬‏ - YouTube or a file of sorts can be used.
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New Member
Dec 27, 2010
Nice post, very helpful, I've put a few bikes together and picked up a few new things from this.
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New Member
May 15, 2011
Al, thanks a lot. Any idea where I can get the clutch cable rerouting gizmo? One of the first things I thought when I opened the kit was "How in the devil is that supposed to work?" Thanks, Jon
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New Member
Jan 7, 2013
Spark plugs

Well i'm having no end of trouble getting my new motor to run, I ran it twice for 5 minutes letting it cool down fully in between, 3rd attempt was a week ago and ive been trying every day since.

I got a reference in another post for spark plug replacements and they said NGK C6HSA, so I bought 2 yesterday only to find that when I got home they are wrong, they have the narrow diameter thread.

Can anyone tell me what NGK plug to get in replacement for the LD Z8C please?


Well-Known Member
Jul 23, 2012
NGK B5HS Spark Plug - hot
NGK B6HS Spark Plug
NGK B7HS Spark Plug
NGK B8HS Spark Plug - cold

extended tip
NGK BP5HS Spark Plug - hot
NGK BP6HS Spark Plug
NGK BP7HS Spark Plug
NGK BP8HS Spark Plug - cold


New Member
Mar 21, 2013
Good info here..what about checking crank connector rod torque,,i know the case needs to be spilt,,but have you ever had a problem with the bottom end on these if not checked,Ive never looked at one?