Front forks too hard

[Drum]

Further to the previous thread by ARJ127, I recently had my front fork seals replaced (in the shop) and my forks are now very unforgiving. When I cross a kerb crossing or pothole it sends a massive shock through the hand grips.

My forks don't have adjustable pre-load. I am thinking the guys in the shop must've put too much fork oil in? Does that sound like a logical answer?

My forks have a bleed screw - can I just bleed a bit out to soften them? Help appreciated.

[R6_kid]

You could bleed a bit out, but as bugjuice found out when he tried this on his 636 it's not as easy as it sounds sometimes!

If they've put thicker fluid in than you had in it last you'd notice a difference, not sure if it'd be *that* different.

[Drum]

Yeah I was thinking it might be hard to stop the bleed once started!

[terbang]

Yup sounds like it and you could try draining a bit out or alternatively completely drain the lot and refill it with the correct spec. The air gap in a fork plays a very important part in the springing as it is a spring in itself. Repalace the air with Oil (over filling), which compresses a heck of a lot less than Air and you will get a hard ride.

[Drum]

Cheers for the advice. Sounds like draining and refilling is the business then.

[Warr]

Check the manufactures recommendation on the oil weight and go buy some of that rate. eg 10W or 15W etc and then drain the forks and full to what the manual says. The manual will hopefully tell you the correct height of the oil when the fork leg is fully compressed with no spring.
That is your starting point. If they are still too hard drop the oil type by 5 eg 15W go to 10W.
If playing with the oil quantity dont go too much more than +/- 30cc's

[Drum]

Cheers for that. I've got the Haynes manual, so no worries.

I've just gotta find a spare set of hands to help get the top bolts back on afterwards!

[Warr]

Cheers for that. I've got the Haynes manual, so no worries.

I've just gotta find a spare set of hands to help get the top bolts back on afterwards!
If you are talking about the problem of screwing the fork caps on against the spring. Here is my method!!
I stand on the bike with a speed wrench, Socket with the crank thing!! and as many extensions as you need so that you can put all you weight onto it. I gets you majourly in the chest so I use some heavy padding, eg large old leather mitten or whatever!!

[Drum]

Cheers for the tip. I'll give it a go.

[erik]

Cheers for the tip. I'll give it a go.
If you suspend the front of the bike, either with ropes from the ceiling or some other way so that the front wheel is off the ground (and therefore the front suspension is fully extended), you shouldn't need way too much force to compress the springs to get the fork caps in?
I use a torque wrench or socket wrench with a bit of cloth padding so I can push it down with my hand while turning it.

[Brian d marge]

What bike what forks?

the airgap is a spring you preload * so to speak * by adding oil .. I use the air gap to max my suspension travel ,,I use a zip tie ,, then take a big hit on the front ,,then when the tie strap moves it will show me the suspension travel

Harshness is what you might be talking about ,,,and untill type of forks are known , oil viscosity is the solution that pops up ...they have uses a heavier weight ... or a thinner wieght and its bottoming ,,

need more info

Stephen

ps If you found any word here spelt correctly ..please RED red me ,,need red ...lots of red

[Drum]

The bike is a ZR750 Zephyr. Not sure what you mean by "type" of forks?? You can see them on my profile pic.

Either way, the answer would seem to be to drain them and refill with the correct amount of fork oil of the correct viscosity.

Cheers, and red rep added!

[riffer]

Let us know if you get stuck. I'm just up the road.

[Drum]

Thanks for the offer. Very kind of you.

[imdying]

Ride it for a week before touching it. Might just be the big change has thrown you off. If they're still not correct, take them back to the shop, you paid to have them fixed correctly after all...

[riffer]

Good point imdying. Another thing to think about, is that the shop has set the forks up to how they are meant to be. You've just got used to having a baggy front end and its just weirding you out that its different.

[Drum]

Nah, I've been riding it for a month or more since the seals got replaced. It's definately not right. I get quite a big hit when crossing a kerb crossing, or even just a pothole, with an audible 'bang'.

The shop (who will remain nameless) took two weeks to cock it up in the first place, and were replacing the seals under warranty - so it didn't cost me anything. I don't want to lose the bike for another 2 weeks (nor deal with their bullshit) so I should fix it myself.

If you ask me, it's pretty disappointing that professionals can't get such a simple thing right.

[riffer]

Doesn't sound like them at all... :mellow: I've had that bang before when I didn't use loctite on the damper rod thread and it came undone. When you went over a bump the forks went to maximum length and the bang was the stop at the end of the stanchion hitting the bottom of the seal. But my forks were baggy as when that happened, so doesn't sound the same at all.

TSS have an extremely good reputation on KB. Deserved too. Give them a chance to uphold their rep before putting them down please.

Is that your bike on Allen Street? Give the bike shop a call and talk to them. Let them know your concerns. I'm certain they'll put you right.

[Drum]

No, you misunderstood me there Riffer. I am saying that I will take it to TSS to get it done properly, not to the OTHER bike shop that cocked it up.

Let me be crystal here: TSS are a bloody good bike shop.

And yeah thats me in Allen St. I take it thats your RF that parks down the other end of Allen St?

[The Stranger]

Stab in the dark here.
Could be the oil too heavy or insufficient air gap, or both.

If the oil weight was upped, I would have thought the rebound would be slower also, you may notice this if you push down on the front suspension whilst stationary and watch it return.

If the air gap is too small (i.e oil level too high) this can manafest as a shudder of head shake under very heavy braking.

Put a cable tie around your inner tube, up against your outer then take the bike for a strop (or over a curb or 2).
How much travel is not being used?

Either way, however at least one would appear to be out and should not be, so they should correct it.

[Brian d marge]

Nah, I've been riding it for a month or more since the seals got replaced. It's definately not right. I get quite a big hit when crossing a kerb crossing, or even just a pothole, with an audible 'bang'.


Ok thats bottoming ..when you hear that band it feels like its metal to metal as in solid??

Then As suggested ,,put a tie strap round the slider

this will tell you if its bottoming , a tin oil will top out as in full extension the same clunk will be felt

Either way its an oil prob

Stephen

asuming they are damper rod forks!!!!

[Drum]

Epilogue:

So the fork oil has been replaced with the right quantity and weight and now the forks are great. The whole bikes handles differently! I didn't realise how bad they were until they were filled to the right level.

On the bright side, I learned to ride with very loose elbows.

[McJim]

I was going to suggest that you eat more pies.

[Drum]

I was going to suggest that you eat more pies.

I'm already on the case.

[riffer]

I'm way ahead of you Damon. You got a long way to go. ;)

Glad to hear those forks are sorted. And riding with loose elbows is never a bad idea. (well, unless they are so loose you can't push the bars, that is).