LCGB Forums

Apologies if this has been covered before. I’m looking at adding an hydraulic front disc brake to my Li Special S3. I’ve watched a couple of You Tube videos (!!) and it looks reasonably straightforward. Am I wrong? Is it do able for a very average home mechanic, or would I be better off getting it professionally fitted??
I’m concerned about drilling the headset and the bleeding, so any tips/advice welcome. Thanks

It's a straight forward job. The only problem is most of the hose supplied with the kits are in my opinion too short. Routing the hose can be tricky but and I always cut a slot in the headset bottom for the hose to sit in as it means you don't need a big hole to accommodate the nut on the end of the hose. As for bleeding make sure you cover any paint work and wear gloves as it will pickle your paint and can cause cancer. As for the bleeding prosses I would go on YouTube it would be easier than trying to explain, but it is very simple

Thanks. Will it be ok to drill the top of the headset rather than the bottom? I’m thinking if I don’t like it, welding the top headset will be more straightforward than the bottom

Yes should be fine but it does depend what angle you can get the connection on the master cylinder at

Revvers wrote:Thanks. Will it be ok to drill the top of the headset rather than the bottom? I’m thinking if I don’t like it, welding the top headset will be more straightforward than the bottom

Slotting the headset bottom offers offers advantages of being neater as the top hides the slot ends but it does weaken it. Therefore the disadvantage of slotting the 'bars' is that they are weakened & easier to snap, even with a low speed tumble.

The neatest way of routing the hose is down through the fork tube (if you can handle the dismantling of the superior braided type) to enable feeding the bare hose through the fork bottom holes (Oooer!)

Bleeding can be frustrating a get on your nerves - a good method- patience and perseverance will work
I use a big syringe and fill it gently from the bottom - then bleed it - ( plenty YouTube videos)

There is another alternative - semi hydraulic where a cable operated the master cylinder is hidden behind the horn cast
Or the Leg shields.
I have one - with careful bleeding and cable adjustment it works fine.
It does Take bit of effort -It get to keep the original headset look

Google Vespa Grimeca semi hydraulic

Thanks for the tips guys. I’m going to give it a go.

there's the other option of under the leggies bud too

If you use the type of hydraulic hose that you can dismantle/make up yourself then you can feed the hose back into lever mounting/housing so that it follows the route of a standard cable in the headset and down to the front hub. Doing this way means no visible drilling of the headset and only a couple of inches of exposed hose at the headset between the master cylinder banjo and where it loops back into the lever/cylinder housing. I think it was Jason Frost who came up with this very neat method of routing the hose.