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faffi

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Everything posted by faffi

  1. Thanks, Jaybird, good video. This is absolutely correct, and very well explained in a simple manner. It is not as dramatic as the video suggest - I think it is about 4 degrees difference between a 130 and a 240 mm wide rear tire, all things else being equal - but it is significant. Not the primary reason on my bike as it has a 120/70 front and a 150/70 rear tire.
  2. Ah, thank you for explaining. The tendency to stand up was very noticeable, I had to use quite a bit of constant force to keep the bike leaned over. Now, if I let go of the bars, the bike will take a little tighter line than the planned trajectory, but quite minutely so. It was reasonably neutral with the Michelin fronts effort-wise, but with the soft front it was difficult to keep a smooth line around corners, the bike seemed to constantly vary lean and trajectory and the bike had to be constantly but gently guided. If that makes any sense. Regarding profile; the Bridgestone had worn rather pointy, with little wear in the center, roughly inch wide, but with the majority of wear on both sides of center, making the tire shape somewhat triangulated until it again got rounded closer to the edges. The Michelins had much more even wear, I only have picture of the profile of the narrow one. The Maxxis appear to have a quite large, flattish section on the center, as seen in my earlier post.
  3. Thank you 😎 The bike has shaft drive so wheel alignment is fixed, but a good thought
  4. There was only 2 mm difference in diameter between the old Bridgestone and the new Maxxis front, so a 1mm difference in height. I made a much bigger actual change earlier when I cut off just over 4 inches of the soft portion of my stock springs to stiffen the front end. This gave me about 15 mm less dive under the same kind of braking, meaning it should also hold the front end up a similar amount higher during brisk cornering. I also changed from 35 to 57 cSt fork oil, which naturally slowed down the rate of compression (and rebound) to compensate for the stiffer springs. Static sag was held the same, though, it is just the spring rate and damping that was altered. Steering felt more direct and connected, if that makes any sense, with the firmer front end. Yet the change in ride height did not change the need for additional lean, although I could lean a bit further before touching down.
  5. Forgot to mention that I now also find myself going on the throttle noticeably earlier than on any other bike ever before, because early throttle application does not push the bike wide. Part is down to having little power, no doubt, but there is zero fighting or insecurity when opening the throttle once max lean is reached and the exit determined. I always felt the need to wait until I began picking the bike up before I began smooth acceleration to avoid running wide, but there is no need for that on this bike at the moment.
  6. Not that this will have much interest to anybody but me, but here is an update anyway 😄 When I bought the bike, it had a new Michelin PR4 on the rear and rather worn PR3 up front. Soon after, I replaced the brake discs and took the opportunity to fit a Pilot street, the mentioned narrower 110/70R17. When the new discs also warped, I fitted the spare wheel with stock, straight discs and a 65% worn Bridgestone BT30F mounted. With all these three front tires together with the PR4 rear, the bike demanded more lean than expected. With the PR3 and PS the bike steered fairly neutral and worked fine also on gravel. The BT30 did not take well to gravel. It also demanded a lot of counter-steering throughout every corner -- every time I relaxed fully the bars, the bike went for upright and a straight line. Unlike the Michelins - the narrow PS had no chicken strips in the end - the BT30 would fold on worn tarmac at peg scraping pace repeatedly, giving a sensation of falling over another 10 degrees (but probably no more than a couple). Each time, it regained grip slowly but smoothly, all I did was relax and wait. You can see the slip marks, which of course went around the circumference on both sides, in this image The PR4, OTOH, had the most even wear across the thread that I have ever experienced - since I only ride on the road, up until now my tires have always been flat to varying degrees in the middle. However, what I really wanted to discuss is the experience I had today on a new pair of tires. A lot of Deauville riders praise the PR2 as superb for the bike, so I decided to try that. Then I read a test of the Maxxis M6029 Supermaxx and went for that up front. Yes, I know many say never mix brands, and preferably not models. But I have done that since 1980, mostly with great results, but also a few that did not work. I have, though, had more tires from the same maker that did not work admirably. So how did the pairing work? Splendid! The only thing not quite perfect is that the bike now want to ever so slightly fall into corners and need a touch of input to straighten up - opposite to what it was, but also to a much, much lesser degree. Confidence and grip was excellent from the moment I left the garage with the fresh rubber, and there was no hint of insecurity or numbness throughout the 200+ mile ride. The rear tire lost any trace of virgin rubber within 10 miles.They even worked nice on gravel. Most interesting, though, is that the bike now require much less lean for any given corner speed, acting similarly to any other motorcycle. How and why I cannot say, but I could corner faster than before but did not scrape once. Peculiar, but also very positive. Maxxis fresh before the ride Ditto PR4
  7. Follow what Hotfoot says. Adding lean and brake is probably as ill advised as adding lean and throttle. At 35 degrees of lean, you have about 80% grip left for braking, IIRC, whereas at 45 degrees it is rapidly closing in on zero. This is under ideal conditions; warm asphalt, warm and grippy tires and with a good rider not spending grip by holding on too tight and/or giving the bike confusing/harsh inputs, which also use chunks of your grip account.
  8. I don't mind if people want to include all running costs in their fantasy 😃 So which one would rate above the other, then?
  9. If you could have any track bike in the world, from the classic era to a current MotoGP bike, but it would also be your only track bike, what would you choose?
  10. As to small bikes - I think I have mentioned it once or twice before, but Kenny Roberts Sr's favourite street bike back around 1985 was a Yamaha 250 Phazer. That was both down to its handling, at the time as close as he could get to his race bikes, and the lack of power that demanded a very high level of accuracy in order to maintain a fast average pace.
  11. I began my city riding days on a limited Honda CB100 back in 1980. The law back then said no more than 7 hp and no more than 50 mph top speed for motorcycles operated by people aged 16-18. From 18-up you could ride unlimited bikes. Statistically, the less powerful bikes are also involved in fewer accidents than high powered bikes. Anyhoo, my riding naturally had to evolve around low power and slow acceleration. Since then, I have never felt the need for lots of power, especially during city riding. If I would have to rely on surplous power to keep me safe, I would consider I had already placed myself in a vulnerable situation. I keep the revs in the lower half of the range, usually the lower 1/3, and expect every driver considering me their target. Despite a history of road crashes (due to knowingly overriding the conditions in rural areas) I rarely find myself under stress in dense traffic, regardless of what I am riding.
  12. Being a mediocre rider with a history of more brawn than brains, I have had to stand the bike up to slow down before continuing at a reduced pace countless times. Sometimes from running out of cornering clearance, sometimes just running out of courage. I have never planned for it or practiced it, it's just a result of my SR.
  13. They often send slow-mo with 1000fps of how the tires move during a race or practice session on TV, and it is amazing how much the tires deform and change shape constantly, especially over rumble strips. If they slow the footage real down and the light is good, you can see it really clearly. This probably has as much to do with the low pressure as with the tire construction.
  14. I am talking about the flexibility of the carcass.
  15. Some seems to relax if they get a ton of information from the tires, others get stressed by it. Luca Cadalora was a rider who only wanted to know about significant issues like actual loss of grip, but I am not sure if he is typical or atypical when it comes to top level racers. Watching how soft current MotoGP tires are, it would seem difficult to get a ton of information about tiny imperfections through them, but I have no idea, really.
  16. Personally, I dislike the constant messaging about what is going on between tire and road. I do not want any of it, actually, so that the only thing I will feel is a reduction in grip.
  17. Note comment about downshifting near the end as well.
  18. From the 1:02 to 2:28 is the part of interest (hope the time stamp made it over) for the topic. I do know my own preference to the point that I find one end of the spectrum ruining and the other end bliss. More specific on how to test a tire's construction
  19. I only ride on the street, and I also make the corners as wide as possible (well, I do leave a foot or two as a safety margin) in order to be able to see as far as possible through the corner. Vision is my main priority, not ideal racing lines.
  20. I also thought we have discussed it earlier, but my (lack of) search skills failed to come up with anything, so I took a chance that the topic was from another forum and new to this one 😳 I am still interested to learn if people have preferences or not. Personally, I cannot see any differences on the chicken strips, so my maximum angle of lean is similar, but I go to my personal limit more frequently and with more confidence to the left.
  21. Do you prefer to corner in one direction over the other? Most riders I know prefer right hand corners. We speculate it is because it means more road to the outside to the riders, which gives the feeling of more run-off area and a greater chance to recover from any errors or slides. Personally, though, I feel more confident going through left hand corners. I presume it is because I can look further through left hand bends, but again it is speculation. Anyway, I was reminded of this again when I had to replace the peg feeler on the left, which was down to about a mm. The one on the right had only lost its hat on the acorn bolt top, despite having been on the bike much longer. So I lean over to my personal limit more often to the left than to the right.
  22. I have always claimed it is much nicer to be first with inferior equipment, regardless of sport, than to come between second and last with the best equipment. But many people in my experience would rather have the best tool, even when it makes them look like one.
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