Team-BHP > Motorbikes
Register New Topics New Posts Top Thanked Team-BHP FAQ


Reply
  Search this Thread
6,445 views
Old 2nd November 2009, 18:12   #1
Senior - BHPian
 
Join Date: Jun 2004
Location: Navi Mumbai
Posts: 1,048
Thanked: 163 Times
Add a 6th gear to a CBZ!

As the thread title suggests, is it possible to add a 6th gear to the CBZ (type 1)? Lot of times i shift in to the non existent 6th gear when on the highway..and always wished there was an extra gear on the bike . Has anyone here done this before? any thoughts anyone?
heavy_foot is offline  
Old 3rd November 2009, 13:02   #2
BHPian
 
ilangop's Avatar
 
Join Date: Jul 2008
Location: Chennai
Posts: 992
Thanked: 903 Times

Hi Heavy foot,
Though I am no bike expert here is one small suggestion.
If you are a frequent highway driver you might replace the rear sprocket with a smaller one so that the wheel revs more. But for this you would need to compromise a bit on torque, or pick up in a bikers language. I guess adding a 6th gear would involve more of research and cost. Or even a larger dia tyre would take you to higher speeds.
-Ilango
ilangop is offline  
Old 3rd November 2009, 14:21   #3
BHPian
 
Rennjit's Avatar
 
Join Date: Feb 2009
Location: Namma Bangalore
Posts: 668
Thanked: 166 Times

Well to say, Impossible is nothing but what are you looking out from such a mod?
Not many have tried as results are far outweighed by the effort, time, cost factors. Its no retrofit job as of now. Sprocketing is a better option to get close to your riding needs.

If you are really in for trying out, consider the possibility of replacing 5th gear set with a new tall ratio set - get something usable from others / rework any from others/ make a set.. its all up to how much you are willing to. Gap from 4th to 5th would increase but if you find new ratio well & good you can replace 4th to even out the gap. This might be a beginning. Do keep us posted.
Rennjit is offline  
Old 3rd November 2009, 18:33   #4
GTO
Team-BHP Support
 
GTO's Avatar
 
Join Date: Feb 2004
Location: Bombay
Posts: 70,501
Thanked: 300,604 Times

OT but related : This thread reminds me of a popular RX100 modification by "Mubarak Auto" at Tardeo (Bombay RX owners will recall). He used to add a 5th gear to the RX100, which quite honestly didn't really make a difference
GTO is offline  
Old 3rd November 2009, 22:57   #5
Senior - BHPian
 
aaggoswami's Avatar
 
Join Date: May 2007
Location: Vadodara
Posts: 4,982
Thanked: 2,931 Times

1) Its not worth doing. I dont think that any reliable modifications are done to gearbox. Adding a gear is not an easy task and we dont know what are the effects on the engine. Best avoided unless you are able to get in touch with someone who modifies bikes for racing. He is the best man you can approach for such modification.

2) From what I have in your post, it looks like you are looking forward to cruising at more relaxed engine rpm. The other way it is possible is to modify the sprockets. However, it depends upon bike and manufacturer how they have done calculations and decided onto sprockets.

IIRC, a few years ago in OD ( OverDrive ) there was a very vast coverage on the effect of reducing reducing rear sprocket size on bikes like Pulsar, Kaz and CBZ. If I am not wrong, installing a smaller sprocket on rear of CBZ relatively gave less effect than adding a larger sprocket on the front.

OD did an extensive test where in they added a larger sprocket on the front, tested the bike and then added a smaller sprocket on the rear with stock front.
This was given as a small booklet in newstand copy of OD.

At the end of the day, I will say that rather than doing modifications in gearbox, its better to experiment a bit with sprockets. First drop two teeths in the rear and then see effect.

Last, dont go overboard on this as engine might be strained. Max, drop three teeths on the rear or at the very limit, 4. Beyond this, the engine will be strained.
aaggoswami is offline  
Old 3rd November 2009, 23:38   #6
Senior - BHPian
 
Join Date: Sep 2005
Location: Adelaide
Posts: 1,159
Thanked: 318 Times

Adding a 5 th gear to a RX does make a difference.

there are some Gear boxes that you may be able to use but let me check what all they are.

We are in procedure to fit a 6 gear in FZ16 just for the sake of it cause we have a gear box that would fit direct and also we are putting in a Kick on the FZ.
desideep is offline  
Old 4th November 2009, 14:04   #7
BHPian
 
lancer&shogun's Avatar
 
Join Date: May 2008
Location: Back in Chennai
Posts: 148
Thanked: 2 Times

Quote:
Originally Posted by aaggoswami View Post
The other way it is possible is to modify the sprockets. However, it depends upon bike and manufacturer how they have done calculations and decided onto sprockets.
Quote:
Originally Posted by ilangop View Post
If you are a frequent highway driver you might replace the rear sprocket with a smaller one so that the wheel revs more. -Ilango
+ 1 Try sprocketing it really works.
Or
How about procuring a 6speed gear box? But we need to find which gear box should fix properly without any major modification.

Just my 2 cents.

Cheers,
L&S
lancer&shogun is offline  
Reply

Most Viewed


Copyright ©2000 - 2024, Team-BHP.com
Proudly powered by E2E Networks