Modern Vespa

A complete disaster while I was trying to change my roller weight.
Impossible to remove this lock nut. I broke the small part that prevent the wheel from turning.

I was then, ok my only solution is now to block the wheel from turning... bad ideas...while blocking the wheel on of the brake. the part to which the brake was fixed to, broke....total disaster.

I'm still left with a lock nut that I can't remove and 2 broken parts.

Where can I found those 2 broken parts (shaft and transmission box) and how can I remove this nut that seem impossible to remove now... I have removed it before but this time...well...


Broken shaft where the lock nut is

Broken transmission cover.


Last edited by reticulum on Fri, 15 Sep 2017 16:29:36 +0000; edited 2 times

I'm having a bit of a hard time picturing what is actually broken.

When you go to remove the driven pulley nut, use the parking brake, AND squeeze the rear brake lever while you undo the nut. Worked every time for me.

Alternately activate the parking brake and use an impact wrench to get it off.

I tried all those things and they were unsuccessful. The driven pulley nut is still there...

what you call the broke transmutation part is actually the gear housing and that is behind the rear wheel. dealer only part. don't forget to order the gasket.

the clutch shaft does need to be replaced as you broke off the 10mm hex part.

now to get the nut off use a air impact only or you can dremel cut the nut in half.

on page 29/82 parts manual

item #1 is the cover and #7 is the driven pull shaft. they list 2 different part numbers for the shaft you will have to ask the dealer which one.
http://www.af1racing.com/store/ProdImages/st3/ETR7000US1.pdf

your looking at $320 in parts

I have never used the hex end of the driven pulley shaft for install or removal of the nut. If you can get the nut off you may be OK. But how are you trying to do the removal? Sounds like you're maybe reefing on the wrong bits....

That's the part I was thinking of. Thank you for the gasket tip I was not sure wether or not I would have to buy a new one.

The hex is not strong at all it snapped very quickly:(

Now, I really need to remove this nut. Otherwise I can't even remove the broken parts.

Thanks a lot for your help. I'll let you know how the repair goes.

you should never use the hex for removal its only for doing the torque when reinstalling.

air or electric impact should do just fine for removal. no need to block the wheel either.

Agree with OAD...
I always thought that Hex was Useless when you consider the Torque Value.

My go to is typically to lock the wheel with Parking Break, or Velcro a strap on the Rear Brake Handle.

I have also seen someone on youtube wrap a bar in a thick sweat shirt, and shove it between to spokes to block the wheel from turning.

Then use the correct socket and a Pri-Bar to get that nut off.

Air Tools are not my favorite choice, I accidentally strip a crank shaft once.
One of my past "Expensive Repair" Lessons Learned.

Keith,
Marietta, GA

Well, the wrap a bar in a thick sweat shirt, and shove it between to spokes to block the wheel from turning is what broke my gear reduction block.

I use this to get my variator nuts off when doing a belt, works great
Milwaukee 1/2" cordless impact.

Impact wrench is the only way to go for removal.

I was using my $25 impact wrench for the job...what a bad idea.
I went to borrow my neighbor's impact wrench (a $350 impact wrench)... The nut came off right away....
I did not know that my impact wrench from Harbor Freight was so weak

Conclusion, my F...ing cheap impact wrench just cost me $500 of parts.

I got one of those, Garbage...
A good impact wrench would not only remove the nut, if set to the wrong direction it would strip out all the threads.

I stick to my previous comments, I use a Breaker Bar to be safe.

Keith,
Marietta, GA

The parts have been ordered but I start to ask myself some questions.

Will I need a special tools to remove the clutch shaft from the bearing?
Do I need to change the bearings? any seal I need to buy ect...

Impact will only strip threads because of user error.

Hey dude, dont worry most diy have broken off this punney end shaft. Its not needed. You can use the rear brake carefully combined with an obstruction in the rear wheel to torque this nut up, and to undo just use an impact.

+1

To be honest you would have to pound on a nut a long time to strip all the threads. Especially on a spline this size.

I have changed the gear box and was able to use the old gasket. The gaskets were in back order and I had to wait a month or more maybe.
After using the scooter for 2 weeks after everything was re-assembled. One day I found a lot of gear oil on the rear wheel.

After cleaning, I was able to pinpoint the leak. It's coming from the wheel shaft that you can see on the picture.
It lets me with a lot of questions. What went wrong? the oil seal is supposed to be new... Was it missing on the new part (even if I think I remember checking the old and new part and they were identical)?

Was there a trick when you re-install everything?

Or, I have been unlucky and the oil seal was bad to start with?


Here is the picture of the new part installed

I don't see the seal, just a bearing. Will try and look at my parts bike when I get home.

there is no oil seal on the outside

Ohhh. I'm talking about the one inside. I'm afraid I have to remove everything again to check it 😔

Always use a new seal. old ones are bedded to the old shafts and will always leak if you reuse them.

as OAD said never reuse seals and gaskets
got the seals bearings and gaskets in stock

there are seals on the inside the bearing comes with a dust seals on the outside

Oh, I agree... I learned the hard way.
Cheep Ass Harbor Freight Electric Impact Wrench.

So far I have not found anything I could not remove with a Breaker Bar.

I have not changed the Belt on my 500 ABS yet, so I may eventually need one. I have a very good Digital 1/2" Torque Wrench that I invested in that handles the 500 Requirements for Tightening; but taking apart I will address in the next 4000 Miles for Belt/Roller Maintenance.

My Rear Tire on the 500 is almost to the bars, and that will be coming up soon. My Original City Grip is just going to make it a little over 5000+ Miles.
I have a second Rim with a New City Grip ready to go on. I may entertain the Car Tire again on the Rim I am taking off.

Right Tightie... Lefty Lucy...
As you told me a long time ago.

Keith,
Marietta, GA

Impacts are for REMOVING nuts and bolts, not installing
You put an impact on a lug nut to tighten it at the dealership I turned wrench at back in the 80's, you would be fired on the spot.

Meh.
I use my impact to spin on lug nuts all the time.
Just lazy of me perhaps.
But when I put on the torque wrench there is always plenty more turn required.

Sure do hope you start them by hand or you will pay for it one day with a thread file.

Of course. A turn or so.

I found the culprit to my oil leak on my wheel.
When I re-installed the shaft inside the oil seal, the shaft being a little bit heavy, I must have kinked the oil seal (see picture).

I do not have any tool to remove it or any spare part to replace it. It does not look too bad when I gave it back its normal shape so I decided to re-install everything and give it a try. Of course this time I took my time to insert the shaft and made sure the oil seal was not kinked.
10 miles later... no leak... fingers crossed.


Oil leak from the outside

Gear reduction opened

Kinked Oil seal

Well, I still have a small leak. I'm going to order the part and change it.

I have ordered the part with a new oil seal but it will have to come from Europe...I've been told 4 to 6 weeks before the part arrives.

I keep monitoring the oil leak and it looks like I do not have a leak anymore. It sounds like it took some time (1 ride) for the oil seal to take back its normal shape around the shaft (after being kinked) and now it is seal tight and does not leak.

Any thoughts...

Id not have bothered to change the broken part. I know three bikes with the end of the shaft broken its not a problem and not really used don't know why they bother having it there really.

just keep monitoring it and when it starts leaking change it.