Drewteague Posted October 6, 2018 Posted October 6, 2018 Hey, everyone! I'm a tech doing a light track day build on a customer's '99 V11 Sport. He complained of no compression damping in the front. I dismantled the left fork, and found nothing excessively worn or broken. I did notice, however, that the cylinder of the cartridge is drilled three times. This allows all the oil to puke out the sides, eliminating most of the damping until the ring passes the last hole, about 3/4 of the way through the entire stroke. This corresponds to the reaction I get from the fork leg compressing it manually, off-bike. Everything I've found indicates that this is the stock setup, and that it hasn't been mangled by someone in a past life. Now, Has anyone plugged or filled any or all of these holes in order to increase overall damping, directing more or all of the oil through the adjustable valve, thereby increasing the range of adjustability? I'd definitely be running 5w if I ended up modding it in this fashion.
docc Posted October 6, 2018 Posted October 6, 2018 GuzziMoto is your man! Let me see if I can scare up his thread . . .
docc Posted October 6, 2018 Posted October 6, 2018 Here's one of his posts discussing his approach. I thought there is a thread on this , but I'm not finding it . . . https://www.v11lemans.com/forums/index.php?showtopic=20247&p=228581 1
MartyNZ Posted October 6, 2018 Posted October 6, 2018 ... I did notice, however, that the cylinder of the cartridge is drilled three times. Now, Has anyone plugged or filled any or all of these holes in order to increase overall damping, directing more or all of the oil through the adjustable valve, thereby increasing the range of adjustability? ... Along with Docc's advice, see Tom M's post https://www.v11lemans.com/forums/index.php?showtopic=17835 for a pretty good answer. Also search for Marzocchi damping. There has been lots of discussion on this in the past. 1
docc Posted October 6, 2018 Posted October 6, 2018 There! Credit where credit is due, TomM! I seem to recall { } images of someone's actual hole block off . . .
MartyNZ Posted October 7, 2018 Posted October 7, 2018 Knumbnutz posted pictures of a welded hole here https://www.v11lemans.com/forums/index.php?showtopic=19648Drew, it will be interesting to hear from you about what you do (just plug a hole, or plug a large hole and add smaller holes) and the results you get. 3
docc Posted October 7, 2018 Posted October 7, 2018 Knumbnutz posted pictures of a welded hole here https://www.v11lemans.com/forums/index.php?showtopic=19648 It will be interesting to hear from you about what you do and the results you get. That's it, buddy! Thank you!
footgoose Posted October 7, 2018 Posted October 7, 2018 Knumbnutz posted pictures of a welded hole here https://www.v11lemans.com/forums/index.php?showtopic=19648 It will be interesting to hear from you about what you do and the results you get. That's it, buddy! Thank you! Dang it. That thread ended without conclusion. I'll follow this to see how Drews turns out. 1
LowRyter Posted October 7, 2018 Posted October 7, 2018 I've been fiddling with the suspension on the Greenie since I got it. I had the rear shock rebuilt (clickers didn't work) and added a heavier spring. That didn't make a huge difference. What I finally figured out was the fork was too stiff, it really bounced on rough roads or when carrying a load with saddlebags. I had previously played around with air pressure but I never adjusted the fork. Then I finally played with the fork adjusters. I took the stiffness out (and set them to "0" when loaded), quite a difference. I had always believed that stiffer is better. Now I know that isn't true. The front is much more complaint now. I never set it up over half stiff now solo and take all the stiffness out when packed and loaded. Now I need to mess with shocks on the EV.
Drewteague Posted October 9, 2018 Author Posted October 9, 2018 Awesome info, everyone! Thanks for all the links. Good to know my intuition was on point. My customer lent his bike to a friend who claimed it suddenly lost damping, but it seems it was always like that. I'll confer once again with the bike owner to clarify his goal (eg. more damping altogether, more progressive damping, etc) to make a plan around hole location/size and fork oil weight. I'll post the results when I have them. 1
GuzziMoto Posted October 9, 2018 Posted October 9, 2018 Awesome info, everyone! Thanks for all the links. Good to know my intuition was on point. My customer lent his bike to a friend who claimed it suddenly lost damping, but it seems it was always like that. I'll confer once again with the bike owner to clarify his goal (eg. more damping altogether, more progressive damping, etc) to make a plan around hole location/size and fork oil weight. I'll post the results when I have them. Sorry I missed this. I was on vacation in Moab. The forks on my wifes V11 seemed OK. But I had them apart to do some servicing, I decided to put them together without the springs to feel what the dampening curve felt like. What I found was that there was zero compression dampening until the forks were near bottom. It was because of the holes in the tube, they let oil flow freely until the pistion was past the holes. It was only at that point that the oil was forced to flow through either the piston valving or the adjuster. This meant that the adjuster only could affect the bottoming of the fork. The rest of the travel the adjuster did nothing. As I understand it there are more than one version of Marzocchi forks on the various V11 models, along with Ohlins. I don't know how the later V11 forks are, but the wifes early red frame V11 forks had no compression dampening until I blocked off one of the two holes on the compression side fork leg. Sadly it has been a few years, so I don't remember the details. But as I recall hers had two holes and I blocked off one of them. I also changed oil viscosity. I found that when I was forcing the oil to flow through the valving I actually needed thinner oil. I think you will be happy with the results. I know my wife is.
docc Posted October 9, 2018 Posted October 9, 2018 There were two different Marzocchi forks on the early Sport (1999-2001), on one: the axle is nutted; and the other: the axle threads into the left fork leg. These are all 43mm USD, as I recall. (there will be another part number in the system for the black finish on the 2001 Rosso Mandello. @Drewteague, can you confirm the build date (left headstock tag, month-year), 10th VIN character (W= 1999, Y= 2000, and the fork type (nutted or screwed in)? (I've never heard of a 1999 Sport in the US. So, it may have a couple other features that might inform your suspension set-up.)
Drewteague Posted October 10, 2018 Author Posted October 10, 2018 There were two different Marzocchi forks on the early Sport (1999-2001), on one: the axle is nutted; and the other: the axle threads into the left fork leg. These are all 43mm USD, as I recall. (there will be another part number in the system for the black finish on the 2001 Rosso Mandello. @Drewteague, can you confirm the build date (left headstock tag, month-year), 9th/10th VIN characters, and the fork type (nutted or screwed in)? (I've never heard of a 1999 Sport in the US. So, it may have a couple other features that might inform your suspension set-up.) It's a '99 by VIN, build date 3/2000. The front axle has a nut, and does not thread into the fork leg.
docc Posted October 10, 2018 Posted October 10, 2018 Hmmm... my 2000 Sport was built 3-2000. Same axle (nutted). Tenth of VIN: W= 1999, Y= 2000Not likely the customer’s V11 will have the earlier, steeper triple clamps. (edited after I got home and looked at my VIN)
Drewteague Posted October 10, 2018 Author Posted October 10, 2018 Success! The damping is much better, and the adjuster screw has a greater effect on the range. I used 5w, but in the future, the fork could easily be tuned with a more viscous oil to suit different conditions. I made a modification gallery with some pics: https://www.v11lemans.com/forums/index.php?app=gallery&album=268 2
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