Modern Buddy

Ok, 2006 Buddy 125 -- 17k miles -- just tried to replace roller weights (with Dr Pulley's) and put in a new belt (kevlar).

This is maintenance I've done myself in the past with no issues (except figuring out how to do it without a impact wrench), but something's really wrong this time and I can't figure out what. (I'm not a mechanic by any stretch... and it has been a while since I've done this...)

I've gone through the whole process and double checked everything I can thing of and still have the same result... When I start the engine with the transmission cover off, everything seems fine. But as soon as I put the cover on and start it, it makes a horrifying noise of metal on metal. Is that enough for anyone to offer possible problems??

Note the pics below are from tutorials and represent things I CAN'T achieve
Two possible (and possibly related) causes:
1) I cannot get the kind of slack shown in this tutorial in this photo



It's all I can do to squeeze it over the crankshaft. Even when using the screwdriver tip
from this tutorial

Is there some other trick to getting the clutch plates to open up to get more slack? Is it a problem that I literally can't force that to happen even using a screwdriver on the spring?


2) I can't get the washer plate to connect with the splines of the crankshaft; it's too far out, which clearly violates these quoted instructions (for the Blur and the Pulley variator, which I was not replacing the variotor, just the sliders)

The left photo is the washer plate, notice the splines in the hole. The photo on the right shows the splines (barely showing) on the engine's crankshaft. When reinstalling the washer plate, make sure the splines match that of the crankshaft splines. This is one of the gotcha's. The outer pulley plate will probably not go in enough to expose enough of the crankshaft's splines to allow sliding the washer plate on (as it is in this photo).

Other possible related issues, maybe?
Anytime I try to kickstart, I seem to remember getting a similar horrifying sound but in much smaller dose. (Could be an inaccurate memory of the sound)
The shop has replaced the starter twice... both times with a used starter.


Any ideas, anyone?

Just ruling out the dumb stuff...are you certain that you're using the correct size belt? When squeezing the rear clutch pulley halves apart by hand, you should be able to get the pulley to sit down in the bottom of the pulley. The belt should then do the work of holding the pulley halves apart. If, with the belt all the way at the bottom of the clutch pulley, it still doesn't give you enough slack up front at the variator, it may simply be that it's too short a belt. There should be numbers printed on the belt, can you list them here?

Without enough slack in the belt at the front variator, you will not be able to get the ramp plate to sit far enough onto the splines to allow the kick start ratchet gear to grab on to the splines (which is what you've been noticing). It also will make it impossible to properly torque the retaining nut down properly, as the ramp plate will want to tighten down at an angle.

I'm going to bet that you have tightened the variator down to the belt and not the boss. When you start the scooter, and the belt moves up the variator, you are hearing the variator pulleys slapping against the boss. You need to really squeeze the belt togther to force it down into the clutch pulleys. You can make a holder like this out of a scrap of plywood and 1/4-20 screws. I added the aluminum after 5 years of constant use. You just need some fender washers on each side. Belt size should be 743x20x30. Japanese Bando is an excellent belt.

Try this: Remove the clutch and belt completely. You should deglaze the pads and clean the bell with brake cleaner when doing this service anyway.

Grab the clutch pulleys, sqeeze together while turning clockwise. Shove the belt all the way in. Put a spring clamp on the belt to hold your slack.

Istall the front variator with belt loosely hanging over boss, and torque to spec (be sure the sliders are installed according to the picture in the package). Be sure the variator halves are up against the boss and not the belt. Don't put the clutch assembly on the rear shaft at this time. Just let it hang while keeping all the slack up on the variator shaft.

You should have enough slack in the belt to get the clutch assembly back on
the shaft. Remove the clothes pin to give you a bit more slack. Be careful to keep the belt shoved deep in the pulley.

Yes, your belt is currently in the way of your variator tightening up all the way. It can be a pain in the butt for sure - getting the belt into the clutch takes a significant amount of grip strength.

My trick is to install the variator hand tight and then make sure the belt can spin free before torquing it down.

DO NOT attempt to drive it unless you know FOR SURE the variator is tightened correctly.

Just ruling out the dumb stuff...are you certain that you're using the correct size belt? .

Haha. Thanks for checking. Yes, I am 99% positive I have the correct belt! I have the 743x20x30, PL30707 -- it's the exact same as the one that came off, except minus the wear and tear, and I got the Kevlar.

Sounds like a consensus that the is issue is my inability to get the belt sufficiently into the rear clutch plates.

And Yes to DeeDee's theory:

I'm going to bet that you have tightened the variator down to the belt and not the boss.

I can confirm that is true.

(I tried for way longer than I care to admit, but I could NOT -- with any amount of effort or leveraging a screw driver on the springs -- get the rear clutch plates anywhere near far enough apart to get the belt further down in there. It felt like a win just getting the belt below the lip of the rear plates.)

I'll try DeeDee's suggestion of removing the clutch completely... and probably see if I can get someone with better grip strength to help out.

Thanks!!

Grab the pulley with both hands and push the belt down into the pulley with your right fingertips. The pulley rotates while opening so just trying to wedge it apart won't be easy.

Once you take the clutch off it's 300% easier to seperate the pulley halves. You can get your fingers in there to get good purchase.

Done!

I don't have an impact wrench, so didn't remove the clutch at this point.

I put a clamp on the belt as close to the clutch as I could get it (similar to DeeDee's picture except on the scooter), then turned the clutch plates clockwise by putting my fingers on the outer plate at the back/rear while someone else pulled on the belt from the front. Moved the clamp in to take up the new slack, turned some more... until I had it clamped with enough slack.

(I've noted that I should get an impact wrench and clean the pads and bell.)

Thanks everyone!!

Good job! Make one of those holders pictured in my post above. A scrap piece of plywood, and $3.00 worth of hardware from ACE. Put the bolts to hold the variator 3 1/8" apart, and the bolts to hold the clutch 2 1/2" apart. Drill a 1" hole in the center. Use 1/4-20 nuts and bolts with fender washers on each side. Leave the screws extend about 1/4" or so. Enough to fit into the dimples on the variator, and the holes on the clutch bell. Using a holder allows you to torque the nuts to spec.

DeeDee wrote:Good job! Make one of those holders pictured in my post above. A scrap piece of plywood, and $3.00 worth of hardware from ACE. Put the bolts to hold the variator 3 1/8" apart, and the bolts to hold the clutch 2 1/2" apart. Drill a 1" hole in the center. Use 1/4-20 nuts and bolts with fender washers on each side. Leave the screws extend about 1/4" or so. Enough to fit into the dimples on the variator, and the holes on the clutch bell. Using a holder allows you to torque the nuts to spec.

Ah, I see. Awesome. Thanks!

Here it is in action on the clutch: https://www.youtube.com/watch?v=cgVLGXMPD1A

... and if you put a stiffer clutch spring in, it's really hard to squeeze!