[Craighjr]

Does anyone have the spec on the stock master cylinder as to how far the stock lever actuates the master cylinder plunger before the return port gets covered? I just installed Puig levers and have to keep adjusting the screw out because the master cylinder is locking up when the brake gets hot. The stock lever uses a different arrangement and I am having a hard time measuring the known good stock part to copy the distance with my aftermarket stuff.

 

[Max Kool]

I know what you mean, and I was wondering the same when I installed my levers. Luckily in my case they didn't need adjustment.

Good luck and be careful!

 

[Hui]

The plunger should have a little free play before acting on the piston, not only do you need to clear the hole but also leave an allowance for the fluid to expand to.

 

[Craighjr]

The plunger on the scrambler is actuated by a 15mm-20mm long steel pill that is a loose piece in the master cylinders dust boot. It also has a few MM of pre-load against it with the stock lever as set up by the dealer.

 

[Derek]

With the cover off the reservoir you should see little swirl of brake fluid emerging from the small hole in the bottom of the reservoir as you release the brake lever. If you can't see this movement of fluid, the return hole isn't being uncovered by the piston.

 

[Craighjr]

I was hoping that would work when I installed the lever but it still locked up. I have been carrying an Allen key with me and have had to back it off twice. It's at the point where the Puig lever has to be in the 6th position just to have some brake. So much for adjustable...the stock lever had more adjustment to it.

 

[Derek]

There is something not right there. If you have that much free travel before the brake is being applied there must be a lot of free play at the plunger. So why is the brake binding?

 

[stavely]

18 months ago I swapped mine for some cheapie chinese adjustable lookalikes off ebay and they work fine.
At this point, if i were you, I would put the original stuff back on and see if the problem disappears.
That way you can tell if it's the Puig stuff causing the problem or something else.
Binding caliper piston, over filled reservoir, wrong puig lever supplied etc.

 

[Derek]

18 months ago I swapped mine for some cheapie chinese adjustable lookalikes off ebay and they work fine.
At this point, if i were you, I would put the original stuff back on and see if the problem disappears.
That way you can tell if it's the Puig stuff causing the problem or something else.
Binding caliper piston, over filled reservoir, wrong puig lever supplied etc.

So did I with no problems. That is good advice, to find out if the problem lies with the Puig levers or the brake itself.

 

[Craighjr]

I put the stock stuff back on and it's fine. I am going to fire an email off to the manufacturer and look for some insight. Worst case is I run the lever all the way out and don't have any adjustment. It is still a nicer lever than stock in appearance and feel.

 

[harrymorrison]

Hello! I don’t have much experience in this field, but I would like to suggest you to contact with McMotoparts experts and ask for guidance. They will definitely help you.

 

[jerbacher]

I have a similar issue and just found this thread searching for my issue. I just put on the Ducati + Rizoma adjustable levers for m797 and Scrambler. Everything fits well and the clutch side works like a dream. The brake lever does not have the set screw to adjust the amount of plunger engagement though, it is just a solid piece with a divot to engage the plunger. Because of this, I have more free travel in the lever before reaching brake engagement and only feel comfortable with the lever in the outermost couple of adjustments due to bottoming out on the grip. The brake system is working fine, no air in the line, no sponginess. Is there a way other than that set screw to adjust the plunger travel?