Technical Discussion Topics related to Technical Issues

Clutchless upshifts?

Thread Tools
 
Search this Thread
 
Old 07-15-2008, 02:57 PM
  #1  
Senior Member
SuperSport
Thread Starter
 
CentralCoaster's Avatar
 
Join Date: Jul 2008
Location: San Diego, CA
Posts: 987
CentralCoaster is on a distinguished road
Clutchless upshifts?

Do you guys upshift with or without the clutch? Or only over a certain RPM?

I tried doing this today, seems very smooth if I time it right and bump the shifter when I back of the throttle, even as low as 4,000 rpms.

The method I reading by Lee Parks is to keep pressure on the shifter prior to backing off the throttle, but that seems to shift it a little too early and harshly before the engine has a chance to slow down into the next gear.

What about wear and tear on the bike? If it drops right in with the same effort as using the clutch, I don't see how it could harm anything.

CentralCoaster is offline  
Old 07-15-2008, 03:04 PM
  #2  
Uhhhhh..huh.huh..Member..
Superstock
 
Springbubba's Avatar
 
Join Date: Apr 2008
Location: Vancouver, WA
Posts: 269
Springbubba is on a distinguished road
I use the clutch on 1-2 and 2-3 almost all of the time. I go clutchless after that most of the time.
Springbubba is offline  
Old 07-15-2008, 03:06 PM
  #3  
Senior Member
SuperBike
 
killer5280's Avatar
 
Join Date: Aug 2004
Location: Atlanta, GA
Posts: 1,802
killer5280 is on a distinguished road
Done properly I don't think there's more wear and tear doing clutchless upshifts. I always use the clutch for 1-2 (and it's still kinda rough).
killer5280 is offline  
Old 07-15-2008, 03:21 PM
  #4  
Senior Member
MotoGP
 
VTRsurfer's Avatar
 
Join Date: May 2008
Location: San Clemente, CA
Posts: 3,451
VTRsurfer is on a distinguished road
In a car transmission you would be wearing the snycromesh gears shifting without the clutch. Motorcycle trans don't use syncros, but still some wear must occur. I don't see the advantage if you are not on the track.
VTRsurfer is offline  
Old 07-15-2008, 03:22 PM
  #5  
Member
Squid
 
SuperMike's Avatar
 
Join Date: Jun 2008
Location: Asheville, NC
Posts: 59
SuperMike is on a distinguished road
I like shifting with out the clutch, and like what has been said it is really smooth if timed properly. I read in a moto mag that it does not hurt anything if done properly. Some of my friends swear that it will wear the lower gears out though. I usually use the clutch for the lower gears.
SuperMike is offline  
Old 07-15-2008, 03:26 PM
  #6  
Senior Member
Back Marker
 
VTRumble's Avatar
 
Join Date: Apr 2005
Location: Massachusetts
Posts: 187
VTRumble is an unknown quantity at this point
Most of the time I only clutch 1-2, if I'm just cruising around, I'll downshift without the clutch also. It takes some practice but can be done very smoothly .
VTRumble is offline  
Old 07-15-2008, 03:33 PM
  #7  
Senior Member
SuperSport
Thread Starter
 
CentralCoaster's Avatar
 
Join Date: Jul 2008
Location: San Diego, CA
Posts: 987
CentralCoaster is on a distinguished road
The bike gears aren't synchronized?

I'll have to experiement with the clutchless downshifts, I hadn't tried that.

I figure whether or not I'm using the clutch I need to learn to match revs properly during shifts to keep it smooth.
CentralCoaster is offline  
Old 07-15-2008, 03:37 PM
  #8  
Senior Member
SuperBike
 
RCVTR's Avatar
 
Join Date: Dec 2005
Location: South Lake Tahoe, CA, USA
Posts: 1,689
RCVTR is an unknown quantity at this point
I normally use the clutch on the street, unless I'm doing a WOT run.

On the track the clutch is a stop and go device. Well, not really. I use it for downshifting and preventing wheel hop when decelerating.

For clutchless upshifts it's kind of like a reverse throttle blip from wide-open. You only drop it a bit. I time it with the shift, rather than preloading the shift lever. You want to be sure the gears are unloaded before the shift happens.

I think it's beter for the transmission than excessively lazy shifts, where you can hear the dogs clunk.

If you watch the on-bike cameras on race bikes, you can see them use the clutch for downshifting, then let it out easily on corner entry.
RCVTR is offline  
Old 07-15-2008, 04:13 PM
  #9  
Senior Member
MotoGP
 
VTRsurfer's Avatar
 
Join Date: May 2008
Location: San Clemente, CA
Posts: 3,451
VTRsurfer is on a distinguished road
Originally Posted by CentralCoaster
The bike gears aren't synchronized?

I'll have to experiement with the clutchless downshifts, I hadn't tried that.

I figure whether or not I'm using the clutch I need to learn to match revs properly during shifts to keep it smooth.
Syncro gears in a car trans are narrow toothed brass gears that line up with the thicker steel gears. Before syncro transmissions you had to "double clutch" to down shift and come to a COMPLETE STOP before shifting into 1st or it would grind.
I've never had an MC trans apart, but I know they don't have syncros. They use "dogs" to engage gears.
VTRsurfer is offline  
Old 07-15-2008, 07:02 PM
  #10  
Senior Member
SuperSport
 
Hotbrakes's Avatar
 
Join Date: Aug 2007
Location: Fredericksburg, VA
Posts: 714
Hotbrakes is on a distinguished road
Name:  straight.jpg
Views: 14
Size:  18.3 KB

No clutch here. On the street I usually use it unless I'm going flat out, which is pretty much never. Once I hit 3rd, it stays there.
Hotbrakes is offline  
Old 07-15-2008, 07:20 PM
  #11  
Senior Member
SuperBike
 
trinc's Avatar
 
Join Date: Feb 2007
Location: Portland, Oregon
Posts: 1,051
trinc is on a distinguished road
on the track i use the clutch up & down. the quick motion helps me keep my gear count. .

tim
trinc is offline  
Old 07-15-2008, 08:01 PM
  #12  
Senior Member
SuperSport
 
Death Cattle's Avatar
 
Join Date: Nov 2007
Posts: 758
Death Cattle is on a distinguished road
i use the clutch in every gear no matter what, even when i wheelie. IMO, the clutch is obviously there for a reason, so i use it.
Death Cattle is offline  
Old 07-15-2008, 08:04 PM
  #13  
Senior Member
SuperBike
 
killer5280's Avatar
 
Join Date: Aug 2004
Location: Atlanta, GA
Posts: 1,802
killer5280 is on a distinguished road
I use it most of the time, both up and down, but when you're really getting on it clutchless upshifts can be both faster and smoother than when using the clutch.
killer5280 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
CANADAVTR
General Discussion
15
06-08-2010 10:34 PM
Darkone22
General Discussion
3
03-06-2007 05:45 PM
blupleous
General Discussion
30
03-03-2007 08:17 PM



Quick Reply: Clutchless upshifts?



All times are GMT -7. The time now is 07:31 PM.


Top

© 2024 MH Sub I, LLC dba Internet Brands



When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.