Zipp 2019 808 Firecrest spoke tension???

[MaxPower]

Hey

Anyone knows what spoke tension zipp goes with on the 2019 Firecrest 808 with 177 hub?

I measured avg 110 kgf on DS and avg 55 kgf on NDS (24 spokes, 2 cross) - which seams a bit low to me. normally i run 130kgf DS and necessary NDS tension for dish.

Wheels are as good as new (a year old) - i bought them used, but they had almost no use. Get brake rub on the rear wheel and would like to increase tension on the spokes, but don´t know if the hoops and hubs will take it?!


Thanks for the help

[alcatraz]

If you have >55kgf with a tire inflated then there's no reason to bother really. It won't change the wheel performance at all.

Leave a greater brake pad gap on the left side of the rear wheel, because the wheel is going to flex farther that way.

Check for play in the hub. Maybe you have a worn out bearing. Also if your endcaps are of the push-on type, ensure proper skewer tension.

[MaxPower]

If you have >55kgf with a tire inflated then there's no reason to bother really. It won't change the wheel performance at all.

Leave a greater brake pad gap on the left side of the rear wheel, because the wheel is going to flex farther that way.

Check for play in the hub. Maybe you have a worn out bearing. Also if your endcaps are of the push-on type, ensure proper skewer tension.

nope, without tire There don´t seem to be play in the hub. bearings are a bit grainy when spinning it up without pre-load (in the hands)
might change the two 6903 bearing. freehub is smooth.

[alcatraz]

Ok. Take care with the drive side. It's easy to forget that those nipples are dry and under a lot of tension. They might get damaged.

[MaxPower]

Thanks for the tip. I´m okay confident, i have had other wheels with sapim SIRS before. I´m just unsure if the hub will take the extra load?

Anyone knows if it is correct that Zipp specs 110 +/- 5Kgf for both front and DS spokes in the current products (thats what i could dig up)?

[alcatraz]

With a tire inflated and no spokes under 50 or over 120 you are fine.

If your left side spokes are already above 50 (with a tire) then there's no real point to cranking the drive side spokes up higher and higher. You just risk damaging the stuff.

Front wheels have a very wide acceptable range as they have good left/right balance.

[MaxPower]

With a tire inflated and no spokes under 50 or over 120 you are fine.

If your left side spokes are already above 50 (with a tire) then there's no real point to cranking the drive side spokes up higher and higher. You just risk damaging the stuff.

Front wheels have a very wide acceptable range as they have good left/right balance.

checked them inflated yesterday. NDS were between 40-50 Kgf (avg 44,5 kgf). DS avg 100 kgf.
Getting more tension on might not be the solution then. Seems like stiffness would not really be changed in any significant way anyway by the small range i could adjust tension - >40kgf should also be enough in regards to full detensioning risk i think (fatigue).

I have some bearings on the way - had plans to change bearings anyway.

[alcatraz]

40 is a bit low. Those spokes are going to break first.

You could tension all the DS spokes by 3/4 turn and the NDS by 1/2 turn.

It helps if you have a good spoke holder and spoke key. The less windup they produce the easier it's going to be.

Do the DS spokes first. If you feel the nipples binding hard by the 2nd or 3rd, then consider aborting.

As you said it won't increase performance but it will protect the wheel in the long run.

Do you suffer from brake rub? Maybe they aren't that flexy.

[MaxPower]

Thanks for the tips

[MaxPower]

DId some turning - avg 52 NDS, 115 DS inflated 7 bar (what i ride). without air avg 57 NDS and avg 120 DS.
I have good nipple tool and spoke holder, so no problem ther, the Park tool TM-1 is just as it is... a good guess (but it is calibrated to the specific spoke (build my own calibtration tool)

Yes for brake rub - but i´m not sure if it was the jump from 55mm to 82mm rim depth or just a zipp thing my first 80mm wheels

[alcatraz]

It is said that very deep rims deflect more, because they're stiffer. I included some info below.

If you have very thin spokes you could swap them, but if the wheel is original then you'll lose some value customizing it.

[MaxPower]

Thanks again
It runs Cx-sprint. So a bit beefier than cx-rays

[MaxPower]

If you have >55kgf with a tire inflated then there's no reason to bother really. It won't change the wheel performance at all.

Leave a greater brake pad gap on the left side of the rear wheel, because the wheel is going to flex farther that way.

Check for play in the hub. Maybe you have a worn out bearing. Also if your endcaps are of the push-on type, ensure proper skewer tension.

Update. Changed bearings. The wheel runs much smoother. The original enduro bearings were gritty.

What i per change observed today though is that the wheel was knocking laterally when pushed to the side. I do the qr normally okay tight.

Hub bearings are seated on the tight sight, meaning the spacer can be manipulated but is not free moving. Bearings in the hub are seated without cranking it of course.

Will try to pull it apart tonight and see if the axle is not seated, suggesting that the hub bearings are not totally seated.

[MaxPower]

Hm. Bearings seated fine. Maybe it is just me, expecting too much tightness of equipment that is supposed to run freely?

[alcatraz]

Knocking or ticking could indicate the bearing got damaged upon installation. Sure you didn't press on the inner race, or used a hammer?

I'm not familiar with the internals of those hubs. Is the axle smooth between the hubshell bearings or does it have those raised edges that the inner races rest on? Sometimes there's a preload adjuster instead.