Help! How have they screwed up my forks?

[Pbassred]

I had my bike booked in for a service anyway so I got them to change the fork oil and fit heavier springs.  - It was horrible.; far too stiff even though the numbers were right. 

Ok, I thought, never mind. Swapped the springs back. Still far too stiff!  So the new stiffness is nothing to do with the springs. I tried re-settling the wheel, but its to stiff to allow me to pump the forks.

What could they do to a bog standard right-side-up fork?  Is there something that they could put in wrong? upside down?

 

Ref:- VFR800  2009  25000miles

[Mississippi Bullfrog]

What fork oil did they use? Not all grades with same numbers perform the same. 

[husoi]

With a stiffer spring you would have a lower grade oil possibly from W15 to W5 to compensate the harder springs.

If they change the springs and same oil you will have that result.

Would it be the case that you will have to get used to the new setup?

[fullscreenaging]

This gives you an idea of what MBF said

 

https://www.scribd.com/doc/80846501/Motul-Forkoil-Expert-Blend-Chart

 

 

A comprehensive article about fluid. 

 

http://www.peterverdone.com/wiki/index.php?title=Suspension_Fluid

[husoi]

Adding to what @fullscreenaging is saying you have to keep in mind that each brand have different criteria for the viscosity reference so what is W10 on Motul could be a W5 on Castrol (as example, I have no idea of the correct correspondence)

[Pbassred]

Guys, You didn't read the post. I put the old springs back in, so viscosity isn't the issue.  They should be back to stock.  I'm looking for something else.

[husoi]

riiiiiight

Could you have filled it up too much?

Too much oil will do that.

[KiwiBob]

If you have put the original springs back in then surely the oil viscosity has to be the issue? Or too much oil

 

Edited July 23, 2021 by KiwiBob

[fullscreenaging]

20 minutes ago, Pbassred said:

Guys, You didn't read the post. I put the old springs back in, so viscosity isn't the issue.  They should be back to stock.  I'm looking for something else.

I read your post. That’s why I gave you the links only relating to fluid. 
You need to find out what fluid the guys that did the work put in. 
My guess is the viscosity is different from the OEM oil that Honda originally put in. Refer to the blend chart I put up as an example. 
This is the logical explanation if you have put the original springs back. Or like has been said there is too much fluid in. 

Edited July 23, 2021 by fullscreenaging

[oldgrump]

Hi @Pbassred, I would start with the oil, when you thought the New springs were to hard did you check the Air gap, after removing them from the forks? Just to make sure that the company did the correct Gap at least!

What was the Oil that the new springs recommended? and how much difference compared with stock set up!

I run 2 VFR800's, 1 with Hagon springs for road use, 1 with stock for track days. The Hagon is 440cc of 5 weight with 145m/m Air Gap, Stock is 457cc of 10 weight with 130m/m Air Gap.

I would probably check what numbers you were given with new springs then remove oil and redo them yourself, or at least check Air Gaps at moment.

And for your information the Hagon setup is a lot harder!

I take it the company only changed springs, so wouldn't have taken forks out and stripped them, otherwise they would have charged you for Seals!!!

Hence they could't really put anything back together wrong!

Edited July 23, 2021 by oldgrump
adding a bit

[Mississippi Bullfrog]

1 hour ago, Pbassred said:

Guys, You didn't read the post. I put the old springs back in, so viscosity isn't the issue.  They should be back to stock.  I'm looking for something else.

Yes, you said you put the original springs back in, but not that you'd drained the oil. So if the original springs are back then it has to be the oil they fitted. Unless you have also drained and replaced the oil as well?

[TimR]

Why not take it back and get them to remedy their mistakes ? 

[Pbassred]

Husio and Kiwibob got it right.  When I investigated what they had done, I measured the oil in the forks wrongly. In fact; there was 50mm too much in the left fork and 100mm too much in the right.  His excuse on the phone was that they measure oil by volume not height. Aside from the fact that there is no final check, he must have got his arithmetics wrong to get it out by different amounts.  As for why don't I take it back for them to fix:- In order to figure out what was wrong, I had to put it right.  Its fixed now.

This is not the first time that I've caught a big mistake by a "trained mechanic".  There is a long game case for investing in doing more of my own wrenching.

 

[fullscreenaging]

Glad you got it sorted. 
Have you had a chance to get out and test? 

[husoi]

Glad you have it sorted  

That's the main reason why most bikers do their own service instead of trusting people that claim being busy to justify their mistakes.

[Pbassred]

Quote

Have you had a chance to get out and test? 

I won't kid you that its night and day.  I pulled out some of the garage's 10W and replaced it with 5W, so its closer to 7.5W.  So, less movement but gets there quicker. Going to linear from progressive I had expected a slightly harsher ride or low level vibration.  There is none.  You would be pushed to tell the difference.  What I achieved is less fork travel.  I have 20mm in reserve instead of 5mm and that's with half the preload wound out.  There is is still some apparent nosedive under hard braking but I think its more a case of the rear lifting, because well, the nose isn't diving as much.  I notice the back either sliding or compressing though.

For posterity: its a K-tech linear 9.5N/mm spring and I weigh 95 KG all up.  The Bike is a VFR800. All testing done on a full tank.

Having exposed the deficiencies of the stock shock, I feel a new thread coming on..........

 

Edited July 25, 2021 by Pbassred
Punctuation

[Stu]

4 hours ago, Pbassred said:

Husio and Kiwibob got it right.  When I investigated what they had done, I measured the oil in the forks wrongly. In fact; there was 50mm too much in the left fork and 100mm too much in the right.  His excuse on the phone was that they measure oil by volume not height. Aside from the fact that there is no final check, he must have got his arithmetics wrong to get it out by different amounts.  As for why don't I take it back for them to fix:- In order to figure out what was wrong, I had to put it right.  Its fixed now.

This is not the first time that I've caught a big mistake by a "trained mechanic".  There is a long game case for investing in doing more of my own wrenching.

 

 

This is why the likes of @megawatt used to get his knickers in a twist when people used to ask where to take their bikes for servicing etc! 

 

His reply was always spend the money on tools and learn to do it and do it right as some "mechanics" don't give a shit! 

 

Glad you have got it sorted 

 

Its as if some places just want to get the job done and back out the door in the quickest time possible and have the next money earner on the bench 

[fastbob]

Late to the party but I would have said the same , too much oil will turn the forks into solid rods . Glad it's sorted now . 

[jedibiker]

Also was going to say about oil, I tried extra in mine once and it was solid, you need the air to cushion,. really sad a garage did that as they charge way more than i expected. i was quoted £70 per side last year so learned how to do it. plus help from here was amazing

[Gerontious]

What I find amazing is that they did the work and didn't test ride the bike afterwards. That is not normal. My own dealership insists on test riding the bike after any work, even a routine service. I think the lesson of this post is if you are having specialist work done, then have it done by specialists if you cannot or aren't willing to DIY.

I trust my dealership for normal servicing that is part of the maintenance schedule. But, nothing else. Im having the bike serviced on Tuesday, but I am using a specialist to change the rear tyre today, as I don't trust the dealership with my very expensive wheels. When I get round to having work done on the suspension, I will take it to a suspension specialist. These kinds of parts don't come cheap and if you are paying for both the parts and the work then its a reasonable expectation that the work is done properly. fitted properly then set up correctly and finally tested. Before the bike is handed back and the bill is paid.