Guest Graham in NZ Posted August 7, 2004 Share Posted August 7, 2004 The following suspension findings may be of interest: Front forks: Specified wheel travel 120mm Compression and rebound damping adjustment provided for only. Factory-set unladen sag 24mm (Ohlins recommend 25-30mm) Factory-set laden sag 35mm (Ohlins recommended 35-48mm) These figures suggest that the fork is sprung firmly, but not excessively so. Recommended settings after road trials: • Compression damping adjustment backed off almost completely. • Rebound damping at half range. Rear Shock: Specified wheel travel 120mm Spring preload, compression and rebound damping adjustment provided for. Factory-set unladen sag 22mm (Ohlins recommend 5-10mm) Factory-set laden sag 45mm (Ohlins recommend 30-40mm) These figures suggest to me that the shock is sprung too softly, but more importantly, is out of balance with the front fork, yet even with the compression damping adjustment backed right off the rear end feels very harsh over abrupt surface changes. I put this down to the bike riding on the damping rather than the spring. I have read that some riders increase the spring preload to improve high-speed stability, which makes sense now that I've seen these figures, as that should bring the rear more into balance with the front. However, even if increasing the preload gives better sag figures, the excessive compression damping remains the real bugbear to be sorted out by re-valving the unit. Other reading suggested that adding two turns of preload to the rear shock is a good move. I did this by moving the locknut and adjusting nuts from above with a long screwdriver after removing the seat and raising the rear of the petrol tank a bit. One turn decreased the unladen sag by 7mm, that is from 22mm to 15mm and the second turn reduced it by a further 4mm to 11mm. From that I guess that another half turn should reduce it by another 1mm - 2mm, which would place it in the recommended range. At the same time, laden sag has gone down from 45mm to 35mm, which is right in the middle of the recommended 30mm to 40mm range, which seems much better. Later I added another 0.5 turn of rear shock preload. This reduced unladen and laden sag by 1mm each, which suggested to me that it had now reached the point of diminishing returns and probably the optimum preload for that spring. So, 2.5 turns of the collar reduced unladen sag from 22mm to 10mm, which is on the soft end of the recommended range, and laden sag from 45mm to 34mm, which is in the middle of the recommended range. Now the real answer would be to fit a heavier spring and to have the impact damping re-valved softer. That would leave the full range of impact damping adjustment to play with as required. Recommended settings after road trials: • Compression damping adjustment backed off almost completely. • Rebound damping at half range. • Spring preload increased by 2.5 turns. Later I set up a friend's V11 to the same settings and we agreed that the bikes both felt much better, even though he weighs 70kg and I weigh 83kg. My greater weight would have been bringing the impact damping into play earlier than his but even at his lighter weight he reported improved rear-end comfort. Link to comment Share on other sites More sharing options...
Guest John Y Posted August 8, 2004 Share Posted August 8, 2004 I really admire you guys who take such a scientific approach to these things! My suspension priority was to lower the bike as much as possible so that I could reach the ground more comfortably - to that end I backed off all the front pre-load and slid the forks up 10mm through the clamps. Damping is at the softer end of the range. At the rear I also backed off the pre-load almost completely and left the damping at around the factory specs. I couldn't tell any difference between the stock settings and my own when riding (although I was worried about the rear shock bottoming with pillion on board - it didn't!); I still have a comfortable, stable and compliant ride at all speeds which is great. Maybe these things don't make much difference at my pace (I like to carve corners although I'm no peg scraper)? But maybe I'll notice it when I attend my ride day at the Phillip Island GP circuit in September....?!? Link to comment Share on other sites More sharing options...
Mr. Bean Posted August 8, 2004 Share Posted August 8, 2004 Thanks Graham! I tried your settings out on my Ballabio. I must say it has a noticeably improved ride now...at least on our crappy Seattle streets. With the settings straight from the factory I was practically getting bounced right off the bike on some of our roads. This is a much more compliant setup. I haven't taken it out on any fast and smooth mountain roads yet so I don't know how it will feel there. Hopefully today... Randy Link to comment Share on other sites More sharing options...
Guest dkgross Posted August 8, 2004 Share Posted August 8, 2004 Randy, when I get my bike back from Moto I one the fuel/sputtering issues are fixed, maybe we could hook up in West Seattle and you can show me how to make these adjustments? (I'm kinda lame mechanically...but I have tools...go figure...) I'm 5'8", 165 lbs.. and, there's always sushi at Mashiko Link to comment Share on other sites More sharing options...
Mr. Bean Posted August 9, 2004 Share Posted August 9, 2004 Sure thing. Just let me know when... Still waiting to hear what's up with your bike? Randy Link to comment Share on other sites More sharing options...
Guest Brian Robson Posted August 9, 2004 Share Posted August 9, 2004 Comon Dave, tell us whats happening with the beast....and the bike as well Link to comment Share on other sites More sharing options...
Guest Graham in NZ Posted August 9, 2004 Share Posted August 9, 2004 Mr Bean Good bike choice there. With the increased rear preload you should also notice better ground clearance than stock, a boon on serpentine roads. When pushed hard the front bottom of the right muffler and the left sidestand foot tend to ground, especially the sidestand. Sidestand clearance can be improved markedly but cutting the rubber stop back with a wet, sharp knife to move the foot higher. The Neptune mufflers I have on my bike are a bit shorter than the stock ones. The reduced length moves the front of the mufflers back about 50mm and therefore up a bit, which also helps with ground clearance there. Regards Graham Link to comment Share on other sites More sharing options...
Mr. Bean Posted August 9, 2004 Share Posted August 9, 2004 Hmmm...as much as I hate to admit it, it will probably be a while yet before the chicken strips on my bike are narrow enough that metal starts touching down! The bike has waaaay more in it than I have. But hey, that one of the reasons I love this bike...you don't have to be pushing the edge of the envelope for it to be fun! Randy Link to comment Share on other sites More sharing options...
Guest Graham in NZ Posted August 9, 2004 Share Posted August 9, 2004 Hi, Mr bean Despite being a conservative rider, I suspect you'll soon find that the stock length chicken strips (hero-blobs, footrest tangs) will not ground before the propstand foot and right muffler front. Early on I fitted longer tangs to ensure they touched first. To establish the length I placed a 6' x 3' sheet of ply against the right side of the tyres where they touch the ground and then pivoted the sheet up until it touched the muffler front. At that point I measured how much longer the tang needed to be and added 3/4" to allow for suspension compression. To be on the safe side I made the tang on the left footrest the same length. I agree with you that these bikes are fun even at modest speeds, unlike so many modern rocket ships. Regards Graham Link to comment Share on other sites More sharing options...
al_roethlisberger Posted August 9, 2004 Share Posted August 9, 2004 ...just to be clear, in North America, "chicken strips" are typically referring to the section along the edges of the tire that is apparently unused do to lack of leaning over The wider the "chicken strips" the more "chicken" one is I am apparently quite "chicken" most of the time al Link to comment Share on other sites More sharing options...
Guest dkgross Posted August 10, 2004 Share Posted August 10, 2004 chicken? Hell..I'm a full blown turkey. thanks, Randy. I'll definetly ping ya. No word yet, Brian...In this case, I'm thinkin' that NO news is Bad news..I hope Micha took me up on my offer to take the bike home and ride it this weekend...maybe I'll hear something tomorrow (as Robbie does his best to talk me out of selling the Guzzi and getting the FJR...hehehe) it's in the mid-80's in Seattle all week..Not having a bike blows Link to comment Share on other sites More sharing options...
robbiekb Posted August 10, 2004 Share Posted August 10, 2004 it's not even italian for crying out loud !!! you'rea microsoftie and thus a defacto millionaire...who care's about the ST4's exhorbetant service interval prices ? personally i'd stick with yer bike, it ran great till you started ff"ing with it... hmm pretty much like mine come to think of it Link to comment Share on other sites More sharing options...
Guest dkgross Posted August 10, 2004 Share Posted August 10, 2004 yeah...I'm blaming it all on this forum. My bike was perfectly fine until I started messin' with it, cuz YOU GUYS told me to. (thanks for the encouragement, Robbie...it helps when the garage is empty). I'm sure my baby will be back home soon, running strong and smooth. Then I can do they dyno run. then I can screw with the suspension. Link to comment Share on other sites More sharing options...
jrt Posted August 10, 2004 Share Posted August 10, 2004 Remember, it's a process not a ending. You're never really done futzing with your bike and that's ok. Sometimes it runs better. Sometimes it runs worse. The experimenting is where the enjoyment should come in. And when it's not running, just remember these immortal words: You're good enough, you're smart enough, and darn it, people like you. J Link to comment Share on other sites More sharing options...
Guest dkgross Posted August 10, 2004 Share Posted August 10, 2004 I just want to feel confidant that I can ride her anywhere, anytime. That's the whole thing that bums me the most now...loosing confidence. but I sure miss her Link to comment Share on other sites More sharing options...
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