yd100 wrist pin sizes different?

Sloppyslopster

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Hi,

So I ordered a windowed piston off of ebay for my yd/ld100 engine and when I tried to put it in I noticed the wrist pin and bearing were both much smaller than my original piston, so I wasn't able to do this. Is that a thing where yd100s have different wrist pin sizes? Also does anyone know where I can get a windowed piston with the bigger wrist pin and bearing. I don't want to use my old piston since its a little banged up and scratched from my old yd100 jug. Thanks!
 
Hi,

So I ordered a windowed piston off of ebay for my yd/ld100 engine and when I tried to put it in I noticed the wrist pin and bearing were both much smaller than my original piston, so I wasn't able to do this. Is that a thing where yd100s have different wrist pin sizes? Also does anyone know where I can get a windowed piston with the bigger wrist pin and bearing. I don't want to use my old piston since its a little banged up and scratched from my old yd100 jug. Thanks!
2 different rod types, so yes there are 2 different wrist pins. 10mm and 12mm.

You got one of the rare 12mm yd100's. They aren't quite as common, but you can find a new one with a bit of digging and searching.

Alternatively, if you want one heck of a power boost you could always do a Phantom 85 cylinder with an ms460 piston. You have an engine capable of running that combo lol.
 
2 different rod types, so yes there are 2 different wrist pins. 10mm and 12mm.

You got one of the rare 12mm yd100's. They aren't quite as common, but you can find a new one with a bit of digging and searching.

Alternatively, if you want one heck of a power boost you could always do a Phantom 85 cylinder with an ms460 piston. You have an engine capable of running that combo lol.
Great a rare engine lol just my luck. I've looked into the ms460 convo before. Think I might have actually have made a post about it before, but I would much prefer to just stick with the ld jug, head and reed valve thing I got going on. Maybe one day ill try it out. Unless its much easier than original thought. I also don't have access to a machine shop/machining tools anyway. I'll take a look around ebay or a dedicated website to see whats available. Thanks again!
 
Actually you know what screw it I might just try and do the swap. Only question is do the phantom 85 stud holes line up?

Also it there a thread that goes into detail on this kind of convo?
 
Actually you know what screw it I might just try and do the swap. Only question is do the phantom 85 stud holes line up?
Phantom is based on the 50mm stud spacing of the YD100.

If you do go that route you will need to order the exhaust for it too. The Phantom exhaust flange studes are a lot wider apart.

Use a Hyway piston with no windows and swap over your current intake and carb. Should make for a nice 5.5hp engine.
 
Phantom is based on the 50mm stud spacing of the YD100.

If you do go that route you will need to order the exhaust for it too. The Phantom exhaust flange studes are a lot wider apart.

Use a Hyway piston with no windows and swap over your current intake and carb. Should make for a nice 5.5hp engine.
Ok thats good to know if I actually through with this. Just found a windowed piston on ebay with the 12mm wrist pin size that fits the yd for 16 bucks so I may just go for that for now instead of dropping 100+ on a whole new top end. Again appreciate the help Impulse.
 
Ok thats good to know if I actually through with this. Just found a windowed piston on ebay with the 12mm wrist pin size that fits the yd for 16 bucks so I may just go for that for now instead of dropping 100+ on a whole new top end. Again appreciate the help Impulse.
Yeah, make sure to get a reed to go with that windowed piston.
 
Hey weird unrelated question but do you guys have any suggestions on a way to convert a beach cruiser to disc brakes? I know there’s adapters online or whatever but I’m not too sure how reliable they are. Especially with the wheels I have. I have the 10 spoke wheels the bbr tuning sells. Thanks.
 
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