Nissin anti dive outboard front disc brake

[ianmoran]

Hello, I've had one of these fitted. All set up correctly, as far as I can tell. On braking, it judders badly , sending vibration up the forks to the handlebars and feels just wrong, spoiling the ride.

Would "softer" pads cure this, or removing the anti dive bracket ? I've got the BGM non-adjustable dampers on the set-up as well.

I've got it set up on disc links btw, in case anyone thinks that makes a difference to how it operates, compared to drum links.

Cheers

[martyn dwane]

sounds like the disc is warped rather than a pad problem

[missing lynx]

Have you checked your forks are correctly tightened as if they're loose that would cause juddering. Personally I'm not a big fan of anti dive set up as it can make the front to ridged and make the front wheel skip on braking

[ianmoran]

Thanks, I'll check the nuts and disc.

[hullygully]

no grease or oil on the disk?
sintered pads?

[Warkton Tornado No.1]

Personally I'm not a big fan of anti dive set up as it can make the front to ridged and make the front wheel skip on braking

Me neither.

That said, I've ridden a few & the placement of the link from backplate to fork leg is critical in terms of angle & the joints involved, which should be of the spherical 'Rose' joint type unless somehow it is thought the front suspension keeps the disc & caliper in perfect alignment

If you think about an anti-dive brake set-up & the usual plates/brackets employed & then the disc itself, expecting perfect alignment throughout the full suspension movement is a bit optimistic IMO

Whereas, the first anti-dive front brakes I saw campaigned by Phil Bevis were an hydraulic (converted from cable standard) inboard disc brake which, to my mind, has much better design to ensure consistent geometry of brake to caliper.

[jonw]

Personally I'm not a big fan of anti dive set up as it can make the front to ridged and make the front wheel skip on braking

Me neither.

That said, I've ridden a few & the placement of the link from backplate to fork leg is critical in terms of angle & the joints involved, which should be of the spherical 'Rose' joint type unless somehow it is thought the front suspension keeps the disc & caliper in perfect alignment

If you think about an anti-dive brake set-up & the usual plates/brackets employed & then the disc itself, expecting perfect alignment throughout the full suspension movement is a bit optimistic IMO

Whereas, the first anti-dive front brakes I saw campaigned by Phil Bevis were an hydraulic (converted from cable standard) inboard disc brake which, to my mind, has much better design to ensure consistent geometry of brake to caliper.

I'd absolutely agree with WT1 on "the placement of the link from backplate to fork leg is critical", get it wrong and it will lock out your front end under braking and cause skipping.

[jonw]

Even better, heres a video...


https://www.youtube.com/watch?v=0dvVIhP-IGY

[ianmoran]

Thanks for that info and video.

The anti dive bracket is set at the "least harsh" position, with the clamp on the fork leg at the lowest position it will go.

Is that not right?

Also, if I removed the anti dive bracket, apart from not having that feature, how would it effect the handling?

Cheers

[jonw]

If you can replicate the final movement in the video i.e. someone grabs the bars and applies the brake whilst you compress the suspension via pressing down on the fork boots, then your anti dive is set up correctly.
If not, you need to look at the angle of the linkage and the free movement of the links.

[Fast n Furious]

Are your steering shaft bearings in good order?

[Warkton Tornado No.1]

Also, if I removed the anti dive bracket, apart from not having that feature, how would it effect the handling?

If the anti dive link/bracket (or whatever) connection of the brake to the fork leg were to be removed/disconnected then the torque of the brake would have to go through the OEM method.

That is, the link peg or stud would have to be used.

Sorry to spell that out as if you are unaware but safety is paramount & other Forum users may not be so clued up.

Whether the brake is anti-dive or not, there has to be a method of preventing the brake operating system from turning with the rest of the wheel when the brake is applied.



I've stated my own bias toward non anti-dive, but it's all down to personal choice. I prefer to 'feel' the dive, particularly whilst braking hard in the wet, as to how far I can squeeze the lever before the wheel locks up. perhaps more skilled riders than I can sense that occurrence with anti-dive fitted.

[ianmoran]

Thanks for your comprehensive and helpful replies.

[ianmoran]

resized to 20% disc brake.jpg

Hopefully you can see my current set up.

My understanding is that the anti-dive bracket is set as low down on the fork leg as possible, with the plan being to have the least snatchiness and most feel. It judders at anything like high speed.

Any suggestions based on the photo?

The dampers are the BGM non-adjustable ones, btw. All new stuff, done 200 miles.

Cheers,

[bennn]

Have you tried it with the bracket further up the fork leg? I have mine set below the damper mount and don't have any issues with judder or locking up..

As a side note, make sure you put a stainless half-nut on the bolts connecting the linkage as they have a tendency to rattle themselves loose

[ianmoran]

Cheers. We've followed Sticky's bookon this, where they recommend setting the bracket as low on the fork leg as possible. I'll give your suggestion a go. Ta for tip on the thing shaking loose.

[bennn]

Let us know how you get on!

Be interesting as I'd read similar things about the anti-dive arm being as low as possible, I tried it on my Nissin setup and it felt terrible until I moved it back up the fork leg... maybe a personal preference thing..

Ben.