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So more on the modification forefront. I have installed a 05 1000 rr on my 97 f3. The install was a breeze for any that are intrested, practically a direct bolt on. I have also installed an f4i body, also not dificult if you take your time. Now a bit more insight into this install I am using kawi 636 clip ons for the conversion to  retain the radial master cyl and cable clutch. But the problem is with the clip ons mounted under the tripple tree the bars hit the body work and riding position is very unconfortible. So I lowered the front end 3/4 of an inch to put the clip ons above the tripple tree. Now the riding position is better and the bike actually feels much more stable and rideable. I know that moving the suspension can change certain aspects of the handling but I have test ridden the bike after the mod and it feels better than ever. Is there a down side to what I have done to my bike that I should look out for?

3/4 of an inch would give u a pretty drastic reduction in trail.  trail numbers are usually in the mid to high 90s (in mm) and u jus reduced yours by about 19mm.... essentially u just made the bike more unstable by a ton.  however, there is no way of knowing how unstable, especially in comparison to your old suspension, without measuring the trail.  feeling the difference wont be accurate since u changed a lot on the bike.  but ya, too little trail could throw u into tank slappers from bumps on the freeway.  read up here http://www.sportrider.com/tech/146_0310_art/index.html and u can even measure it yourself if u have an inclinometer.  but ya, u might want to look into some heli-bars.

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Naked 93' F2...... RIP -- 04/12/07
04' 600RR Black - currently stuck between track and street usage
- Brembo Master, Sato's, & Ohlins out back

I guess the thing that I am confused on is the old front end and the new front end are very close to the same height. the old front end had the clipons above the tripple from the factory and now the I have the new front end with the clip ons above the tripple. So the overall change would not actually be 19 mm would it? Thank you for the link to the artical. I'll read up on it and see if I can find compairsons to make measurements?

u reduced the trail about 19mm from when the 1000RR forks were flush to when they were raised.  theres no way of knowing how much change that equates to when compared to the original suspension w/out measuring something.  u can get a ballpark figure by measuring the length of the forks from top clamp to axle... each mm shorter here reduces the trail by about a mm.  also, measure the offset in the triple clamps, and each mm less here increases the trail by about a mm.  the RR forks should be shorter, but the triple clamp should also have less offset. 

oh, and the RR forks were not designed to have the clipons above the top clamp, unlike say F4i forks, so thinking that the trail is similar just because the old forks had the clipons above the clamp wont work.  im going to be very surprised if you havent drastically reduced the trail.  anything more than 15mm less than the F2 suspension would cause me to worry. 

one other factor i forgot to mention... u r using a 120/70 front tire on the new front end, as opposed to the 120/60 on the old one??  luckily, this will increase your trail by a lil less than 10mm

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Naked 93' F2...... RIP -- 04/12/07
04' 600RR Black - currently stuck between track and street usage
- Brembo Master, Sato's, & Ohlins out back

So in automotive terms are we speaking of something similar to caster? The angle of the front forks in corilation to a 90 deg angle straight up from the point of the centerline if the front axle? and the length of this distance on the ground is the 80 to 90 mm you have mentioned in a previous email. This sounds correct to me because the tire aspect ratio being taller or shorter will effect this measurment.  I will poise my next question if my reasoning and understanding is correct? I dont mean to challenge your understanding on this. only to devolope a better understanding of how this works and to find out what adjustments need to be made to better the handling now and in the future of this and all future motorcycles.

Thank you again for any and all advice and taking the time to help out a "noob"
Chuck

So in automotive terms are we speaking of something similar to caster? The angle of the front forks in corilation to a 90 deg angle straight up from the point of the centerline if the front axle? and the length of this distance on the ground is the 80 to 90 mm you have mentioned in a previous email. This sounds correct to me because the tire aspect ratio being taller or shorter will effect this measurment.  I will poise my next question if my reasoning and understanding is correct? I dont mean to challenge your understanding on this. only to devolope a better understanding of how this works and to find out what adjustments need to be made to better the handling now and in the future of this and all future motorcycles.

 thank you again for any and all advice and taking the time to help out a "noob"
Chuck

yes your thinking is mostly correct.  caster angle would be a misnomer w/ motorcycles... the term is usually "rake" but essentially it refers to the same thing, the angle of the forks in relation to the vertical.  trail is a term not used so often w/ cars because the suspension design makes the two, caster and trail, proportional.  however, trail on a motorcycle is also affected by the offset in the steering stem and offset in the front wheel.  so w/ a bike uve got 3 dimensions to give u geometric trail... triple clamp offset, tire radius, and rake. 

by changing the front end of your motorcycle, uve dramatically modified all 3 variables... the 120/70 front tire has a larger radius than the 120/60... the forks are shorter (esp since youve raised them in the clamps) and therefore have a smaller rake angle... and the triple clamp has a 2mm smaller offset IIRC.

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Naked 93' F2...... RIP -- 04/12/07
04' 600RR Black - currently stuck between track and street usage
- Brembo Master, Sato's, & Ohlins out back

Stangmx135.... I never tire of reading your posts, they are always packed with useful information!

From the sound of all that, the wheelbase has shortened too which would allow it to turn in faster - assuming the lack of rake doesnt cause it to wash out.

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01 Aprilia Falco SL 1000 - Ohlins, Derestricted, SL Carbon, Chip'd, 520 Conv. Flies!!!

94 CBR 600 F2,F3 Engine,F4i Guages/Body/Tank/RamAir,Short Shift Kit,14/43 Sprockets,DynoJet Stg 1,K&N, Yoshimura RS3, V&H PowerPack, 520 conv,Sliders, O2 Sensor - and Sold it! more ...