Yamaha LB50 PW80 Carb Upgrade and Stock Carb Comparison

In this video I show the change in performance that came with upgrading my LB50's stock up jetted carb to a PW80 clone carb.
You can read more about this swap as well as other Chappy information at: www.mopedarmy....

[@joescambait]

I had a blue Chappy 25 years ago ... we got it to hit 39....40 with a good breeze lol .. thanks for the memories

[@HunterSkiff]

awesome in blue! can get to 41mph maybe with a light breakfast ;-) thanks for the watch and sharing your story!

[@wayneschaffer8305]

I have one exactly like this that I've had for almost 30 years. Unfortunately the engine/transmission is in pieces. My dad and I started working on it when I was a kid because the gear shift jammed and wouldn't let it shift out of neutral. In the process of tearing it apart, we broke a few things and that's where we stopped. I think it would need a complete engine/transmission but have no idea where I would find the whole assembly. It's just sitting in my dad's basement where its been for since we took it a part. I have all the parts that we took off. I'd like to put it back together but I don't know where to begin finding parts.

[@elmski]

I like your videos . greetings from philippines

[@HunterSkiff]

Thank you for the support all the way around the world!

[@mikewiremt]

Nice LB50!! I have an LB80 and am getting back to working and restoring it with some new parts. Just found the MLM parts and they look interesting, might go with a couple of things there - thanks for posting!

[@HunterSkiff]

Hey man, myself and others have compiled a lot of good information on LB50 and LB80 Chappys on Moped Army.com, under the performance section, under the Chappy thread. There is also a Chappy Champ facebook page with a lot of good info on there as well. Keep me posted on the restoration process!

[@mikewiremt]

@@HunterSkiff very cool, I will look for threads there and also on FB - thanks for sharing those resources!!

[@antongeceg143]

Nice and interesting video.

[@HunterSkiff]

Thank you for watching!

[@noreaster4194]

Got another question for ya, is it possible to bolt on foot pegs on these pedal model LB50s? Because the pedal assembly on my LB50 is missing some key components, thus flops around scrapes the ground and the most of the pedal parts are near impossible to find. I'd love to get rid of the pedal assembly and just have pegs.

[@HunterSkiff]

I don't have the bikes in front of me but I believe I looked into this and the answer is yes. Like you mentioned you'd have to ditch the factory pedals, which you and most people are happy to do. The stock and/or MLM foot pegs should work. I will confirm this in a few days and get back to you!

[@jackrutherford-1]

OMG, that's a totally different bike with that pw80 carb.

[@HunterSkiff]

This aint your Grandma's LB50 anymore!

[@jackrutherford-1]

@@HunterSkiff I'm looking for new front sprocket for lb80. Did the front sprockets vary throughout the years. Did you find a source and is it different for lb50 than lb80? Thanks. Niche claims this one will fit my 76 lb80 - www.ebay.com/itm/NICHE-420-15-Tooth-Front-Drive-Sprocket-1963-2006-Yamaha-PW80-DT100-MX100-YL1/293472024293?fits=Year%3A1976%7CSubmodel%3ALB80%7CMake%3AYamaha&hash=item44544bb6e5:g:1AYAAOSwoCFeQ4CQ

[@HunterSkiff]

@@jackrutherford-1 ive used JT sprockets on both my lb80 and lb50 with no issue. they seem to be the exact same. here is a link to one, but theyre available from multiple sellers. www.ebay.com/itm/15T-JT-FRONT-SPROCKET-FITS-YAMAHA-LB80-CHAPPY/274139710245?hash=item3fd4000325:g:hh0AAOSwRl1d8mzy

[@stevereid7140]

Can you show a link to the carb you installed? I have a Chappy 50 that I'm trying to get running. Its been sitting for 35 years.. It turns over just fine, so I thought I would give it a go to get going, but the carb is all seized up.

[@HunterSkiff]

Yes it is this carb. NEW Carburetor for YAMAHA PW 80... www.amazon.com/dp/B00KLKPYX2?ref=ppx_pop_mob_ap_share. You will have to thin the provided plastic collar ever so slightly to fit the carb over the factory intake. Easy job, can be done with sand paper

[@bluckq]

I will be getting a chappy next week. The motor runs fine from what the guy said. I was thinking of either keeping it stock or going with a Pw80 engine swap just to have the 4 speed manual transmission. Do you happen to know what's the top speed for a chappy with a Pw80 engine? Looking to cruise around 37-40mph without having the engine rev too much

[@HunterSkiff]

Sweet! Cruising 35-45 on an LB80 or lightly modified LB50 is possible and I do it all the time. Recently stator on my LB80 has been giving me issues and I’m going to swap in ignition system from PW80. If I can find a complete engine I’m going to do the entire engine swap. To answer your question about speed for PW80 engine I don’t know but a stock LB80 or an LB50 with polini kit can get you the speeds you’re looking for without revving it to the moon

[@noreaster4194]

Are you able to run premium pump gas (93) with the puch 70cc hi compression head - old style fins? I saw you mention in one of your replies

[@HunterSkiff]

Yes. The bike will actually run on regular 87 octane. No issues with pre-detonation

[@carlosdavidgalarza9338]

Hello man, I got a question, how did you bore out the pw80 carb? Ive never bore a carb before but i know you have to bore it from side to side (innlet to outlet) and it has its limits because of the slide, for example a pwk 28 you can only oval bore it, top and botom 1mm and sides cant even touch it because slide would not seal when closed. Grettings from Ecuador

[@HunterSkiff]

I honestly had no plan as this is the first time I've done one. I used a carbide bit to rough in the shape, then used a small sanding drum to make it smooth, going slow and trying to make the shape round lol. You are correct you cannot exceed the slide size obviously. If you have something round to use as a reference, you can see how close your shape is to being perfect. If you have a 3D printer you can make a nice jig. It is not a science, just go slow. Let me know how it goes!

[@shanemarkus6824]

Just bought a Chappy 1975 yellow how do i know if it is a 50cc or 80cc?

[@HunterSkiff]

Congrats! They're fun bikes. The displacement is on the cylinder and on the vin tag

[@kotsioschristou8472]

Hello from Cyprus i just order one same carb and i wanted to know what settings worked on your carb?

[@HunterSkiff]

Hello from USA! I used the stock carb jets, but with the needle in the top position

[@matthornung7850]

Love the video! Did you have to change the throttle cable or the jetting on the pw80? Thanks!

[@HunterSkiff]

Thanks for the support. I was able to use the factory throttle cable. Also, the stock jetting on the PW80 clone carb worked right out of the box, maybe 1-2 jet sizes too rich but it runs very well and usually see cylinder head temps of around 300-330*F during sustained 35-40mph riding.

[@matthornung7850]

@@HunterSkiff Awesome! I'm ordering one today, I think my stock carb is too far gone.

[@HunterSkiff]

Sounds good! Let me know if you have any questions along the way!

[@matthornung7850]

@@HunterSkiff it worked perfect and it runs so well. I just had to use my old curved piece from my carb for the throttle cable. Thanks for the help!

[@HunterSkiff]

awesome! awesome! awesome! glad it worked out. Get out there and enjoy that chappy!

[@antongeceg143]

Could you tell what cylinder head you used, please? It seems that it's not the genuine Chappy cylinder head. Greetings from Germany

[@HunterSkiff]

Wow thank you watching all the way from Germany! Hello from USA! The cylinder head is off a Puch moped, specifically it is the "puch 70cc hi compression head - old style fins" available off of Treatland.tv the head has similar appearance to the factory head, but is cut to match the 45mm piston used with the Polini kit on the bike. Hope this answers your question and thank you for the support!

[@antongeceg143]

Great. This answers my question sufficiently. Thanks and have a good one.

[@HunterSkiff]

Likewise! have a great weekend

[@chrismarino6255]

What did you run as far as main jetting?

[@HunterSkiff]

the jet is labeled 115, but that is most likely not equivalent to a 115 mikuni jet, for example

[@nastynatesscooters9896]

Can you put a pw80 carb on a lb80? What’s a good replacement carb for the lb80 can I use a vm20?

[@nastynatesscooters9896]

My idle jet broke in my original carb and I can’t get it out!! So I just need a new carb

[@HunterSkiff]

I have not messed around with a PW80 carb and an LB80. My guess is that it can be made to work, if it isn’t a drop in swap already. A VM20 can work but you will need a different intake manifold (treatland.tv sells a good one from MLM) but it will stick up through your center plastics

[@jaycoulombe4769]

Is that carburetor still going strong ?

[@HunterSkiff]

Running like a champ!

[@jaycoulombe4769]

Nice, I just ordered one for my lb80.I hope I have the same luck.