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I really enjoy your posts on this forum. I'm not at all trying to start an online argument.... I'm just trying to understand? Maybe "I don't know, what I don't know?" I've looked at the above diagrams, and it doesn't make sense to me??? It seems to me that if you "lower" the the length of the upper tubes (and still don't raise the fork tubes in the triples), aren't you still effectively changing the angle of the steering head, and modifying the geometry of the bike? I seems (to me) that your method of lowering the front end, would give the front suspension less travel, and still modify the OEM steering geometry? Please help me understand what I may not know??? Thank you in advance :cool: -
 

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The method shown has been used for decades to shorten the overall length of the fork assembly. It does not change geometry, it just makes the fork shorter. There is no impact on the angle of the steering head at all, as long as the rear is also lowered at the same time. Lowering only the fork in any way, is not recommended alone, as the change in rake and trail are undesirable.

Yes, this method does reduce travel - and that is the goal and a good thing. When you lower the front of a bike, you are essentially moving the front wheel upward toward the lower triple clamp, sort of like it is hitting a bump forever. The reason to do the lowering by shortening the fork, is that the fork on the R3 has roughly 5.1" of travel when stock, and only 5.3" of space from the front fender to the lower triple clamp, and only 4.7" to the horn and bracket. If you lower the bike by 1" to 1.5", without limiting travel, you have the potential to crash the fender and tire into both the horn bracket and the lower triple clamp - as the travel will then exceed available space for the fork to compress fully (hard braking + load + bump = crash). Installing the lowering spacer as shown, reduces the front end travel under compression by the amount lowered, so there is no issue of interference under full compression. This is why this method is used.

To avoid any changes in front end geometry, lowering the front in any manner has to be done in conjunction with reducing rear ride height an equal amount - preferably with a shorter shock absorber to match the front end being shortened. The rear has the same clearance issues, but with only .25" of space available under full compression. If the shock is not limiting travel by the amount lowered, like happens with the cheap lowering block kits, there is a potential for the rear suspension to travel the full 5" of shock travel, within the remaining 3.5" to 4" of space available before the tire hits the inner fender and rear fender or fender eliminator.

Lowering the rear and front equally will maintain the rake angle of the bike as stock, which will maintain trail as well. To avoid any undesirable effects on R3 handling, both the front and rear of the bike should be lowered equally. Too much lowering of the front will result in a bike that feels less stable, and opens the door to head shake at speed or under hard braking. Too low in the rear and the bike will feel sluggish and slow in response.

Lowering a bike is a compromise with implications you cannot avoid safely. Do it right and the resulting change in handling is minimal, and risk of undesirable side effects reduced (although the lower CG, and reduced ground clearance is another topic).

Cool?
I'm still trying to wrap my head around this idea..... What am I not seeing???? If you change the over all length of the fork assembly, you will effectively change the angle of the steering head (just like raising the fork tubes in the triples). I'm a Journeyman Steamfitter, and do complex angle calculations every day. There are a LOT of variables at work in this front-end equation. I'm not saying I'm right, I just want to understand what I may not be seeing... And, I'd like to hear from @NinjaBraap on this too! I want to understand what doesn't make sense to me? I'm NOT picking an online "fight", I truly want to understand what doesn't make sense to me at the moment. Please help me understand :cool:-
 

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It would make sense if you are increasing the spring rate of the "shortened" spring.... That makes sense, as the travel would be reduced. I'm just lost in what is the difference between shortening the length of the fork assembly, compared to raising the fork tubes in the the triples. It seems like the net result would be the same to me- as far as changing the steering geometry....
 

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A sincere thank you to both @GoFaster & @KevinW 2017R3 for "entertaining" my questioning attitude...... I value both of your opinions as, you are appear (to me), to be @ both ends of the "spectrum", and a good balance between track & street. I ride both, and always want to learn how to improve my riding experience :cool:-
 

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Thank you to all that replied to this post.... I honestly, didn't want to start an online debate/argument. I REALLY do want to learn for myself, as well as help others achieve a smile when riding a YAMAHA R3. We are lucky to have a forum like this to exchange ideas!!!! :cool:
 
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