Front Wheel Hop? R1 calipers and EBC HH.?

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Joken

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So i took my bike for a ride today after changing to r1 caliper and ebc hh pads,
When i put the front brakes on the front wheel hops and pulsates?
I scuffed the rotors prior to new pads.?

About the front ens:

I have the 17" cycle one off front wheel with rotor adapter, with stock rotors, progressive front springs, dropped 2 inches and race tech emulators..
The bike is basically new to me and the front end was done when i purchased, i have only added the r1 calipers and pads,
Never really got a chance to drive it with the factory calipers and pads so unsure if the addition of r1 and hh is the problem.
There is also a odd clunk in the front end when it comes to the end of compression.
Unsure what to try?

Thxs in Advance
 
Wheel "hop" is generally associated with a bad tire, wheras the pulsating braking would most likely be a warped rotor, or two. You could dismount the rotors, and retighten them, being sure there is nothing but smooth, flat surface on their mounting area.
 
So i took my bike for a ride today after changing to r1 caliper and ebc hh pads,
When i put the front brakes on the front wheel hops and pulsates?
I scuffed the rotors prior to new pads.?

About the front ens:

I have the 17" cycle one off front wheel with rotor adapter, with stock rotors, progressive front springs, dropped 2 inches and race tech emulators..
The bike is basically new to me and the front end was done when i purchased, i have only added the r1 calipers and pads,
Never really got a chance to drive it with the factory calipers and pads so unsure if the addition of r1 and hh is the problem.
There is also a odd clunk in the front end when it comes to the end of compression.
Unsure what to try?

Thxs in Advance
You scuffed the rotors or the pads? Any air in the forks?
 
Tire is very low miles and a pirelli angel st,
Checked and air pressure is good, no feathering
Scuffed the rotors
Set the pads, it has just 140 km on them now...
I have had many bikes and this is my second vmax and i have never had this type of problem before...
 
A clunk at the end of compression? Check your rad grill as with 2 inches drop you are pushing it on clearance. Clean and Lube your rotor bobbins as well to free up the rotor. You may also have uneven push on the caliper pistons were they clean with no pitting? We're the forks properly refurbished
 
Okay today i put a few pounds of air to see if that would do anything....its hard to say , but i would say NO
It was making a clunk sound when i released the brake now? and the forks were rebounding?
Rad is fine ( not getting hit)

Well because i bought the bike used, i have decided to pull the front end a part and see what is going on inside,
Previous owner said progressive springs, 2 inch lower and emulators.
So unsure of oil weight and i am close to 235ibs i am going to go with 15w, ( the emulators spec sheet for vmax says 20w?)
What is everyone else using with this combo?
New Yamaha fork seals going to get ordered...along with fork oil...
Any other ideas?

On another note when i first bought the max , when started cold would register 60 on the coo oil pressure gauge.
Last winter i opened her up to see if the oil seal was bulging ... and yes it was.
So i ordered the Kawasaki o-ring and made the bracket suggested from the vmax uk site
Now when cold it is hitting 70... :)
 
I weigh 185 lbs. and used 10 wt. fork fluid with my Progressive fork springs (no emulators) but I know a lot of the heavier guys used 15 wt. and like it.
 
Well got a chance to take my front forks apart today and it doesn't look like anything he said is in the forks
It looks like someone cut the lower springs and they don't even match, and the fork springs look like single rate? and the space measures 9, 5/8" and was level with the top of the forks when i took the caps off.

Pictures added what do you guyz think?


 
Last edited:
Yep Nothing looks vmax at all.
The lowering springs are cut offs of springs and are not even the same?
Contacted the guy i bought it from and he said he paid a shop to install progressive springs and emulators. and now understands why they went out of business...
He said he is going to send me progressive springs kit, just waiting for a reply
 
Yep, that's a mess;

1) Looks like the reason for the extra top-out springs was to lower the forks. But they should be the same left and right.

2) Straight rate springs are not stock and not Progressives. They may be Race Tech, as Race Tech does use straight rate with their Emulator kits (although they forgot to put in the Emulators).

3) Looks to me like they did do the drilling on the damper rods, as required when you do Emulators (but again, they forgot, or cheated their customer, and didn't put in the actual Emulators).

Vinnie
 
Yeah, i am unsure what do to about the holes in the dampener rod,,
should i weld them up?
what size are they suppose to be?
how many?
The PO is sending me the progressive kit with lowering spring. :)
Thxs
 
Yeah, i am unsure what do to about the holes in the dampener rod,,
should i weld them up?
what size are they suppose to be?
how many?
The PO is sending me the progressive kit with lowering spring. :)
Thxs

No, no, no..... don't weld up those holes. You don't need to or even want to.

Those holes were drilled out larger on purpose. The reason is that when you use Emulators, you want the Emulator itself to control the compression damping. The stock holes are small, because the small restrictive hole, along with the fork oil, controls the compression and the rebound damping.

With Emulators, the compression holes are made larger so that all the compression damping is done with the Emulator module and not with small/fixed opening holes.

With an Emulator kit, the 'rebound' is controlled with the thickness of the fork oil used (and with that oil passing through the very tiny 'rebound' holes located way higher up on the damper rods), and the 'compression' is now (after the stock holes are enlarged), controlled with the Emulator valving. That's how the Emulator kit works.

So to me it looks like whoever was working on those forks before you, was on the right track, but then never installed the Emulator. So as of now, you have little to no compression damping in those forks.

Just install an Emulator kit, get the proper top-out springs put in (both the same for right and left fork), and then pick out some fork oil and put it all back together.

When you get an Emulator kit, you'll see the instructions that show you to drill the damping rod. But from the looks of it, it's already done for you by the previous owner.
You're already half way there.

***Oh,,,,, and check inside the lower fork legs to see if the plastic bottoming spacers are in there. If not, get 2 new ones and look at the manual for how they install on the bottom of the damper rods. Don't put those forks back together without them.

Vinnie
 
By bottoming out spacers do you mean the part that go between the bottom of the dampener and the bottom of the fork leg, where the bolt from the bottom leg bolts to the dampener? I can see them in there but was unsure if i wanted to replace the-seals if not necessary? So i have not pulled them right apart as that is the only part left in there.
As for the emulators, i do not have the funds to buy, that is why i was going to weld them up.
I can weld them up for free and the emulates cost around 200 bucks in the great white north.. :)
 

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