my chassis findings

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I just thought that I would leave some information about what I have found on my MVF4. I have set up more that a dozen bikes, all which achieved significant improvements both by the riders and myself. After getting my MV up and down, I switched to Pirelli Diablo Corsas. I have heard several people fear that a 70 series on the front hits the radiator. For those of us iin the US a 65 seiries is only available at the present in one tire in one compound, so if you don't like it you have to change profiles. I first ran the 208 GP Dunlops and was not finished with the set up when I encountered some things that I did not like, none of which was related to front tire clearence. Switching over to the Diablos, I thought that I have serious problems with the bike. I spent the next four weeks working with it, changing setup, suspension tweaking, tire pressures ect. I reached a point where I was begining to give up with stability. Now I may not be the fastest guy out there, but I can hold my own on a track. I found the bike very twitchy and unstable at "normal" speeds and worse the harder that I pushed it. I have a fettish with the Italian chassis because of their predicatbility and stability, especially in corners. More than one person suggested that I throw out the rear shock and buy another brand. I considered this and looked into it. Rear replacement rear shock for the MV is in the $800-1200 range. I had a hard time believing that the Sachs was worse then the stock Showa on the Ducati chassis. By the way, everyone also told me the same about the Duc. I hever had a problem with it! I found myself in a dilemma. I got smoother and more precise with my riding habbits, but I never really knew what the bike was going to do or when. Knowing that during any set up or testing only one thing at a time should be changed. I opted to switch the tires back over to the Dunlop 208 GPs. This is a 120/ 70 front and 180/55 rear. Without changing anything else the bike turned into a vault. Stable, predicatable, and tracktable. Some people say that heating up these tires takes too long, but I almost never ride for less than 1/2 hour and when on the track by one or two laps they are fully up to temp. Riding on the Pirellis was like riding a Japanese bike. It is fine if you like that kind of loose or slipery feel, but it is not my thing. I would have to compare it to riding on Silicone tires. Perhaps I rely on a stable chassis to make up for my shortcomings or maybe it is just the way that I like it. I don't in anyway condem other tires since each is designed for a different purpose. I don't say that the way that I have set my bike up is better for anyone but me. I would find it difficult to believe that I am on the only one who feels this way. Before posting attacks on this just know that I am simply letting you know what I have found. I hope that this last 6 weeks helps someone besides myself.

-- Cali-Kane (mvagusta@sbcglobal.net), August 06, 2004

Answers

Thanks for the info ...... by the way, what settings are you using for damp, comp, preload, ride hieght ? Dan

-- Dan Ginther (dginther@valleysoftisp.net), August 07, 2004.

What I believe is happening is that the rear height is set to high...U did not mention your weight or tall u r...the tire choice for me now is power pilots... they r ouststanding...I weight 125lbs and I'm 5'5...The tires just transform what was good handling be4 to an incredible faultless ride...lots of feedback ...if u think the shock is not up to par send it to Lindemman and tell them how much u weight etc and how u ride and when u get it back u won't believe that thats the same unit ...good luck

-- Rui C. Gomes (1rui@verizon.net), August 08, 2004.

loose or slipery feel? The Diablo's? Hmmm.. I experienced the EXACT opposite. Very slippery feel with the Dunlops..front and rear.. stable as if it were on tracks with the Diablos.. Will NEVER buy another pair of the primitive, French made Dunlops..

I can only theorize that it's a difference in riding technique...

-- Pirate (Pirate@acelink.net), August 10, 2004.


Thanks for the input all! I am curious about the fact that pirate is feeling the opposite. I did everything I could to stablize this bike with those tires. Perhaps I am not sliding the bike all over enough, though it really felt like it could go anywhere at any time. I presume that you are a really big guy. I only weigh in about 160 lbs and don't generally side bikes. I have heard that the sliding part of the Pirellis is quite predicatable, but I prefer a planted feel. Are you doing something to the chassis that I should know about? I have only been riding hard for about a year and getting better all the time. I am open to suggestions, and yes I have more schooling lined up as well as track time. Thanks for the suggestions.

-- Cali-Kane (mvagusta@sbcglobal.net), August 11, 2004.

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