Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

PW80, from everything I read, bolts up fairlt easily.

Or, TTR110

Re: The Official Yamaha Chappy (LB50) Thread!!!

shayne zroback /

Thanks, were is everyone getting their parts? Cables fuel lines, kick start etc?? Ebay or a website?

> Dirty30 Dillon Wrote:

> -------------------------------------------------------

> PW80, from everything I read, bolts up fairlt easily.

>

> Or, TTR110

Re: The Official Yamaha Chappy (LB50) Thread!!!

Treatland.tv

Re: The Official Yamaha Chappy (LB50) Thread!!!

shayne zroback /

Thanks

Re: The Official Yamaha Chappy (LB50) Thread!!!

Robert Schmitt /

For my ttr 110 swap I had to cut off the intake manifold and reweld it together so that it faced backward. It was pretty awful to weld. I didn't know aluminum could have zinc in it, and there was a lot of zinc in it.

If your going to do a swap buy the entire donor bike.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

SO:

I opened up the trans on my Chappy for the first time, looking to eek out the issues I was having, which included the floppy kickstart, bad clutch engagement/sticking etc.

For all those wondering, these trans' are very overbuilt, with huge gears and really large, robust clutch pads.

IMG_20190128_192121_298.jpg

As you can see it takes continuous springs like a ZA50/Tomos A35/55. My first experiment is going to be cutting these down a bit on the first gear to see if it solves my sticking clutch issue. Barring this, Tomos springs are actually only about 3/4" shorter... so maybe the stock replacements stretched, or the aftermarket stiffer springs will work well.

As for the KS lever sag: This was actually a really easy fix. The KS shaft has the ability to rotate with out the spring attached. When disassembling, it is easy to lose orientation and therefore, spring tension. When putting it all back together, rotate the KS shaft clockwise until the gear stops itself, and then pull the spring over and hook it on the tab that's cast into the case. Excuse my lack of pictures, but just remember: all the way clockwise, and then make sure the spring has tension on it when idle.

Another common problem I read in this thread and other is the second gear shuddering/grinding.

This is most definitely caused by the failed one-way pawls in the second gear main assembly pictured below.

IMG_20190128_192150.jpg

While the center, splined chuck is removable and maybe replacable, I am thinking that if you have this fail, the best option is probably to weld that sucker. Although I am curious whether this means that you lose bump start, or the bike now won't roll backwards either...

I am going to attempt to shorten the stock springs and see how that changes my first gear clutch engagement. IF positive, I may grab a Tomos blue spring and enhance from there. I found that even the way it is, second gear kicks in at a good RPM range, so I may leave second gear clutch the same.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Yer a gentleman and a scholar

Re: The Official Yamaha Chappy (LB50) Thread!!!

Glad I found this thread. Picked up a '77 Chappy LB80 this weekend. Bike is all stock and in very good condition, low miles. I have a MLM people's pipe and 30 tooth rear sprocket (32 stock on my bike) in the mail and should be here next Tuesday. Bike does 42mph stock (165lb rider). Can't seem to find any footage of a Chappy with an MLM pipe online so I will be filming my own and posting online for people to see.

Anybody know what size the factory carb on an LB80 is? Minor research seems to indicate its 19mm? Can anyone form this? Additionally, assuming stock carb is 19mm, would there be any advantage on upgrading to a VM20 with MLM intake? MLM VM20 intake from treats looks like it would extend up through the stock plastic fairing.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

MLM intake definitely require cover removal/modification.

Re: The Official Yamaha Chappy (LB50) Thread!!!

I have an extra cover so I wouldn't mind cutting a section out to clear the intake and carb if there is going to be more than a marginal increase in power going to from the alleged 19mm stock carb, to a VM20.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Brandon Weiss (Detective brandon to you) /

Speaking strictly from a size standpoint, i don't think there is much to gain going from a 19mm to a 20mm carb....unless the original carb is of inferior design.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

> Hunter Skiff Wrote:

> -------------------------------------------------------

> I have an extra cover so I wouldn't mind cutting a section out to clear

> the intake and carb if there is going to be more than a marginal

> increase in power going to from the alleged 19mm stock carb, to a VM20.

Honestly, I don't see much being gained. Only an even more pronounced drop in gas mileage

Re: The Official Yamaha Chappy (LB50) Thread!!!

That’s what I’m thinking. I’ll update this thread with jet selection and if I encounter any problems with tuning the stock carb after pipe install but I don’t anticipate any problems.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Jack Rutherford /

the revival of this thread has revived my Chappy desire

Re: The Official Yamaha Chappy (LB50) Thread!!!

> Jack Rutherford Wrote:

> -------------------------------------------------------

> the revival of this thread has revived my Chappy desire

It's about to be really active now that I have one to mess around with. Theres not enough information online on these bikes!! That needs to change

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

> Hunter Skiff Wrote:

> -------------------------------------------------------

> > Jack Rutherford Wrote:

>

> > -------------------------------------------------------

>

> > the revival of this thread has revived my Chappy desire

>

> It's about to be really active now that I have one to mess around with.

> Theres not enough information online on these bikes!! That needs to

> change

Lack of aftermarket support is really a killer. One kit, a few pipes, and a cdi are about it.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Just got my MLM People's pipe in today. Filmed a stock pipe vs MLM sound and ride comparison which is rendering now for Youtube. Install was super simple. Of note YOU WILL NEED the stock exhaust gasket. Without it the flange won't seal up in the slightest and is an air leak party. Tone is very deep and bassy. Not much louder than stock. I have other MLM pipes and theyre notorious for hitting hard at high rpm. This pipe seems to hit at a much lower RPM. Pipe makes a very noticeable increase in midrange punch. Top speed increased from 42 to 54 mph on the same small stretch of road. Im sure it has another 5mph in it, even with the stock gearing, if I had more room. I will link the video once its online.

IMG_9862.JPG

Re: The Official Yamaha Chappy (LB50) Thread!!!

Jack Rutherford /

sweet!

Re: The Official Yamaha Chappy (LB50) Thread!!!

STOCK VS MLM PIPE

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

To follow up with modifications done to the LB50 clutch:

Shortened stock spring actually gave me a nice little boost at take off, but honestly not enough to have me keep up with NYC car traffic, so I am going to track down a tomos blue/yellow spring set and see what kind of off-the line hauling I can make happen.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Jack Rutherford /

what are your sprocket tooth counts? a number of sprocket/chain kits are offered on ebay

Re: The Official Yamaha Chappy (LB50) Thread!!!

Bike has stock gearing, 15:30. I ordered a 28 tooth rear sprocket from treats but haven’t installed it yet. Bike could use a lot more gearing. Engine is revving pretty high at 55mph. Has the power to pull off taller gearing

Re: The Official Yamaha Chappy (LB50) Thread!!!

Going to replace tires and tubes on my Chappy next week. Anybody have any tips for getting the split rims to separate from the bead of the old tire? It was an absolute bear to change the tires on my CT70 which uses similar style split rims. I only have access to hand tools. Any advice would be appreciated.

Re: The Official Yamaha Chappy (LB50) Thread!!!

"puch 45mm O-RING high compression head" came in today from treats. It is advertised to fit Yamaha Chappy but unfortunately does not fit mine. Stud spacing, center to center, on my stock chappy head measures approx 51mm and on the Puch O ring head, 45mm. As such it doesnt fit. Posting here just as a heads up

IMG_9956.JPG
IMG_9958.JPG

Re: The Official Yamaha Chappy (LB50) Thread!!!

Hopefully you have informed Treats about the discrepancy .

Re: The Official Yamaha Chappy (LB50) Thread!!!

> P D Wrote:

> -------------------------------------------------------

> Hopefully you have informed Treats about the discrepancy .

Yup, I’ll put the resolution once I get response from Treats

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

The LB80, AFAIK, does not share the same stuff spacing as the LB50 chappy

Re: The Official Yamaha Chappy (LB50) Thread!!!

> Dirty30 Dillon Wrote:

> -------------------------------------------------------

> The LB80, AFAIK, does not share the same stuff spacing as the LB50

> chappy

Yea I think that's where this discrepancy is coming from. Anyone want to measure the stud spacing on his/her LB50?

Re: The Official Yamaha Chappy (LB50) Thread!!!

Jack Rutherford /

just drill that bitch out like treats did on the PuchHonda head

As a matter of fact, I wonder if that PuchHonda head fits - bet it's close (edited)

Re: The Official Yamaha Chappy (LB50) Thread!!!

Jack Rutherford /
IMG_5998copy.jpg

nothing a little drilling wouldn't fix

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