Need a little guidance on lowering/stretching - Kawasaki ZX-10R.net
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 24 Old 06-28-2011, 02:04 PM Thread Starter
Squid
 
Join Date: Jun 2011
Posts: 39
Posting Frequency
 
Need a little guidance on lowering/stretching

Hey whats going on guys?

Looking for a little direction for setting the bike up for some straightline stuff and general riding.

I am very new to the powersports stuff so forgive any ignorance

The bike is a Gen 1

-1 front
Full Arata System
Tuning and stacks coming soon

Also building a custom direct port nitrous setup to spray it until it makes 200hp.

What factors decide on what you need as far as stretching and lowering? Im looking at trying to figure out what I need to know to decide what level of lowering and stretch I need.

Does over all suspension setup Change it? Rider weight? Tire?

Or is it simple a question of how much power you make?

Trying to make an educated decision but I don't know where to start.

Thanks for any help guys!
Sponsored Links
Advertisement
 
post #2 of 24 Old 06-28-2011, 02:28 PM
GP Rider
 
09zx10miami's Avatar
 
Join Date: Jul 2010
Location: In the woods
Posts: 1,130
Posting Frequency
  
I'm not lowered and I'm making 242hp on spray....but I only spray 4th -6th gear.... Otherwise the bike wants to come str8 up.....as far as lowering that's up to your personal preference ...the lower you go the less agile your bike will be...

****Giiiiiiiiittttttuuuurrrdooonnneee****
09zx10miami is offline  
post #3 of 24 Old 06-28-2011, 02:34 PM Thread Starter
Squid
 
Join Date: Jun 2011
Posts: 39
Posting Frequency
 
Quote:
Originally Posted by 09zx10miami View Post
I'm not lowered and I'm making 242hp on spray....but I only spray 4th -6th gear.... Otherwise the bike wants to come str8 up.....as far as lowering that's up to your personal preference ...the lower you go the less agile your bike will be...
I have thought about really getting after it with some spray. I just dont know enough of what the gen 1 drive line will handle.

Are you stretched at all?

Im just curious what balance of lowering and stretching will get it stay hooked up and not facing the sun.
Sponsored Links
Advertisement
 
post #4 of 24 Old 06-28-2011, 04:38 PM
Champion Rider
 
quikgix's Avatar
 
Join Date: Oct 2006
Location: Visalia ,CA
Posts: 374
Posting Frequency
Images: 3
   
Quote:
Originally Posted by [email protected] View Post
I have thought about really getting after it with some spray. I just dont know enough of what the gen 1 drive line will handle.

Are you stretched at all?

Im just curious what balance of lowering and stretching will get it stay hooked up and not facing the sun.
When I had my 05 10R i used a #34 jet dry shot spraying before the air filter
and it made 201 hp at the rear wheel. I still have a few custom maps from those days.

Now what

Last edited by quikgix; 06-28-2011 at 04:40 PM.
quikgix is offline  
post #5 of 24 Old 06-28-2011, 04:53 PM Thread Starter
Squid
 
Join Date: Jun 2011
Posts: 39
Posting Frequency
 
Quote:
Originally Posted by quikgix View Post
When I had my 05 10R i used a #34 jet dry shot spraying before the air filter
and it made 201 hp at the rear wheel. I still have a few custom maps from those days.
Awesome.

Where you lowered or stretched at all?
post #6 of 24 Old 06-28-2011, 04:57 PM
Certified SLOW
 
nolaZX10's Avatar
 
Join Date: Jun 2004
Location: San Antonio, TX
Posts: 3,131
Posting Frequency
           
Are you building this for just drag racing or just the street as well? 1/4 mi or 1/8 mi?

Best 1/4mi ET: 8.98 @ 147 (stock motor, no turbo/nitrous)
nolaZX10 is offline  
post #7 of 24 Old 06-28-2011, 05:15 PM
Supercharged Mod
 
Join Date: May 2004
Location: Toronto, Canada
Posts: 4,388
Posting Frequency
         
I did a lower/stretch on my gen 1 to make it a better drag bike, but I still wanted to keep it streetable with acceptable steering and suspension characteristics. No nitrous, and no plans to.

Started with some math: wanted to be near the top of 5th gear at the end of a quarter mile, and with some estimates of what the trap speed ought to be, that led to the gearing selection. I prefer to do all the ratio changing with the rear sprocket. I ended up at 17/45 (stock is 17/39) and "actual field experience" has been that this seems about right. Keep in mind that not only is this no nitrous, but also no power adders at all. If you have major power adders then use a different estimate of trap speed, and you can always go through at the top of 6th rather than 5th, crunch the numbers.

Now some estimating: 17/45 ought to accelerate about 15% harder than 17/39 (45 divided by 39).

To compensate, we need to make the bike 15% less "wheelie-prone" and a bit more for good measure. If the center of gravity height stays the same height then the distance (in the fore/aft direction) between the center of gravity and the tire contact patch needs to be 15% more (plus a bit more, just to make sure). The C of G of the combined rider and bike is a little rearward of halfway between the front and rear wheels (i.e. about 26ish inches ahead of the stock rear wheel contact patch). Add 15% to get it to where we want it to be and it sounds like a 4 inch stretch. My target was 5 1/2 inches and this is without any lowering.

If you have major power adders that result in the engine making more torque than stock then it needs to be factored in just like the above.

If you want decent steering characteristics for normal road riding then lowering needs to be minimized and you need to keep suspension travel (including the sag measurement) in a normal range. In particular, with the front suspension at full compression, the front fender must not collide with the upper fairing or radiator. If you want to maintain full suspension travel then this sets a boundary on the amount you can lower the bike, and it isn't very much! 10 millimeters or thereabouts. That's what I did.

Now it gets tricky; you need to set nominal rear ride height such that it keeps the rake and trail in the same range as stock. The down-angle of the swingarm will raise the rear if you just extend the swingarm, so you need lowering links - in combination with ride-height shims.

I used swingarm extensions, fixed-length lowering links (I seem to recall that they give about 2" lowering if installed without doing anything else), 190/55 rear tire, and some washers under the upper shock mount to fine tune the rear ride height. Initially I used three 1/8" thick washers but I'm now at two 1/8" and one 1/16" washers - I fine tuned this based on how the steering felt.

It took some fiddling with ride-height washers and spring preload to get it worked out but I'm happy with the end result. Steering feel during normal riding is almost normal; it's a wee bit slower/heavier than standard but it's not a bother. Cornering clearance is still good (because it's only lowered by about 10mm ...), suspension compliance seems same as stock (because full compression and rebound travel is available), it doesn't bottom on bumps any more so than it did when stock, and there is still at least *some* swingarm down-angle to give at least *some* anti-squat geometry. And the front fender won't collide with anything, and the suspension will hit mechanical limit before the oil drain plug smacks the ground ... it probably has enough ground clearance to drive off a normal kerb, although I'm not about to try it (again, it's only lowered 10 mm).

It is never going to have as much grip exiting corners as a stock-wheelbase bike. But for a street ridden bike ... it's fine and is actually a silly fun street bike, because the shorter gearing lets the engine get into the power band at sane road speeds ... and because it doesn't steer like a school bus.

A bike with more extreme power adders will need more stretch and/or more lowering ... and more rear tire grip to avoid spinning the tire on takeoff.


Helibars, MRA screen, Ohlins damper, reversed shift pattern, sorted suspension, braided lines, Michelin Pilot Power, all else stock 'coz it's fast enough!

Last edited by GoFaster; 06-28-2011 at 05:18 PM.
GoFaster is offline  
post #8 of 24 Old 06-28-2011, 05:17 PM Thread Starter
Squid
 
Join Date: Jun 2011
Posts: 39
Posting Frequency
 
Quote:
Originally Posted by nolaZX10 View Post
Are you building this for just drag racing or just the street as well? 1/4 mi or 1/8 mi?
Both. No track days (road racing) for me, but I just don't want to kill the overall feel of the bike to be ruined.

No set length on the track. I will probably re-gear for some of the longer events.
post #9 of 24 Old 06-28-2011, 05:19 PM Thread Starter
Squid
 
Join Date: Jun 2011
Posts: 39
Posting Frequency
 
Quote:
Originally Posted by GoFaster View Post
I did a lower/stretch on my gen 1 to make it a better drag bike, but I still wanted to keep it streetable with acceptable steering and suspension characteristics. No nitrous, and no plans to.

Started with some math: wanted to be near the top of 5th gear at the end of a quarter mile, and with some estimates of what the trap speed ought to be, that led to the gearing selection. I prefer to do all the ratio changing with the rear sprocket. I ended up at 17/45 (stock is 17/39) and "actual field experience" has been that this seems about right. Keep in mind that not only is this no nitrous, but also no power adders at all. If you have major power adders then use a different estimate of trap speed, and you can always go through at the top of 6th rather than 5th, crunch the numbers.

Now some estimating: 17/45 ought to accelerate about 15% harder than 17/39 (45 divided by 39).

To compensate, we need to make the bike 15% less "wheelie-prone" and a bit more for good measure. If the center of gravity height stays the same height then the distance (in the fore/aft direction) between the center of gravity and the tire contact patch needs to be 15% more (plus a bit more, just to make sure). The C of G of the combined rider and bike is a little rearward of halfway between the front and rear wheels (i.e. about 26ish inches ahead of the stock rear wheel contact patch). Add 15% to get it to where we want it to be and it sounds like a 4 inch stretch. My target was 5 1/2 inches and this is without any lowering.

If you have major power adders that result in the engine making more torque than stock then it needs to be factored in just like the above.

If you want decent steering characteristics for normal road riding then lowering needs to be minimized and you need to keep suspension travel (including the sag measurement) in a normal range. In particular, with the front suspension at full compression, the front fender must not collide with the upper fairing or radiator. If you want to maintain full suspension travel then this sets a boundary on the amount you can lower the bike, and it isn't very much! 10 millimeters or thereabouts. That's what I did.

Now it gets tricky; you need to set nominal rear ride height such that it keeps the rake and trail in the same range as stock. The down-angle of the swingarm will raise the rear if you just extend the swingarm, so you need lowering links - in combination with ride-height shims.

I used swingarm extensions, fixed-length lowering links (I seem to recall that they give about 2" lowering if installed without doing anything else), 190/55 rear tire, and some washers under the upper shock mount to fine tune the rear ride height. Initially I used three 1/8" thick washers but I'm now at two 1/8" and one 1/16" washers - I fine tuned this based on how the steering felt.

It took some fiddling with ride-height washers and spring preload to get it worked out but I'm happy with the end result. Steering feel during normal riding is almost normal; it's a wee bit slower/heavier than standard but it's not a bother. Cornering clearance is still good (because it's only lowered by about 10mm ...), suspension compliance seems same as stock (because full compression and rebound travel is available), it doesn't bottom on bumps any more so than it did when stock, and there is still at least *some* swingarm down-angle to give at least *some* anti-squat geometry. And the front fender won't collide with anything, and the suspension will hit mechanical limit before the oil drain plug smacks the ground ... it probably has enough ground clearance to drive off a normal kerb, although I'm not about to try it (again, it's only lowered 10 mm).

It is never going to have as much grip exiting corners as a stock-wheelbase bike. But for a street ridden bike ... it's fine and is actually a silly fun street bike, because the shorter gearing lets the engine get into the power band at sane road speeds ... and because it doesn't steer like a school bus.

A bike with more extreme power adders will need more stretch and/or more lowering ... and more rear tire grip to avoid spinning the tire on takeoff.
Great Post. Thanks much for such a response. I will definitely keep this in mind as I weigh out the options. It sounds like we both had similar ideas about how we wanted the bike to perform.
post #10 of 24 Old 06-28-2011, 07:45 PM
Champion Rider
 
quikgix's Avatar
 
Join Date: Oct 2006
Location: Visalia ,CA
Posts: 374
Posting Frequency
Images: 3
   
Quote:
Originally Posted by [email protected] View Post
I have thought about really getting after it with some spray. I just dont know enough of what the gen 1 drive line will handle.

Are you stretched at all?

Im just curious what balance of lowering and stretching will get it stay hooked up and not facing the sun.
I lowered it with 3 hole links in the lowest setting, then lowered the front end about 1-1/2 and used a strap to pull it down til it almost hits the top of the fender. And the bike was at around 65" wb

Now what
quikgix is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki ZX-10R.net forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
stretching and lowering 2005 zx10 frizzle The ZX-10R 20 06-19-2011 09:55 AM
adjustable kickstand, lowering strap kit, lowering links Satan Parts, Gear and Accessories 5 10-01-2010 10:35 AM
NWS- Stretching is Important! JUPJON Adult Content - Photos / Videos - N.W.S. 11 08-13-2008 09:55 PM
Noob with guidance from INDY AlexxScott Welcome Newbies! 22 07-25-2007 08:23 PM
Stretching it? GARSZX10R Parts, Gear and Accessories 13 05-16-2007 06:17 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome