CBR 600F 1987 - 1990 CBR 600F Forum

Problems running without fairings

Thread Tools
 
Search this Thread
 
  #1  
Old 06-17-2010, 09:11 AM
mrfisher's Avatar
Member
Thread Starter
Join Date: Mar 2008
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
Default Problems running without fairings

Last season, the fairing tabs which had been JB-Welded on by the previous owner failed while I was on the expressway. I watched in horror as the entire left side fairing ripped away and fluttered down the pavement, where it was promptly demolished by a semi-truck following behind me. Needless to say I'm running the bike naked now, but I've noticed an engine problem when I do. When I'm running at speed under constant throttle, the bike seems to lurch back and forth a bit, like it's losing and then gaining power again. I'm guessing this is due to excess air ingestion.

Has anyone built any baffles or something to prevent this when running without fairings? What can I try to fix this?
 
  #2  
Old 06-17-2010, 11:46 AM
JesseAwesome's Avatar
Senior Member
Join Date: Jun 2010
Location: Oregon / 503
Posts: 743
Likes: 0
Received 0 Likes on 0 Posts
Default

Why don't you just rejett to take advantage of the additional air flow. Even better yet, get a K+N filter, and an aftermarket exhaust and put it on the bike, THEN rejett. You'll get a notable power gain!
 
  #3  
Old 06-17-2010, 01:23 PM
tripicana's Avatar
Senior Member
Join Date: Nov 2007
Location: Colorado Springs
Posts: 557
Likes: 0
Received 0 Likes on 0 Posts
Default

it has been reported, that covering the intake air holes halfway with tape, will cure your problems.
 
  #4  
Old 06-17-2010, 01:24 PM
tripicana's Avatar
Senior Member
Join Date: Nov 2007
Location: Colorado Springs
Posts: 557
Likes: 0
Received 0 Likes on 0 Posts
Default

my left side fairing did the same departure from the bike. luckily i was able to go back and get it.
 
  #5  
Old 06-17-2010, 04:22 PM
JesseAwesome's Avatar
Senior Member
Join Date: Jun 2010
Location: Oregon / 503
Posts: 743
Likes: 0
Received 0 Likes on 0 Posts
Default

Interesting how covering the hole halfway does the trick... makes sense though!
 
  #6  
Old 06-17-2010, 11:03 PM
thrasher572's Avatar
Senior Member
Join Date: Jan 2008
Location: Alberta,Canada.
Posts: 1,554
Likes: 0
Received 0 Likes on 0 Posts
Default

The idea is to reduce the turbulance, not reduce airflow...
 
  #7  
Old 06-17-2010, 11:36 PM
KongBastard's Avatar
Senior Member
Join Date: Apr 2009
Location: Port Coquitlam, BC
Posts: 197
Likes: 0
Received 0 Likes on 0 Posts
Default

I do not have fairings on my CBR. The problem is at high speed, not necessarily at full throttle. Turbulance plays a part as does air flow. This is a very common problem on the CBR.

I have sealed both of the holes in the frame (one side has my ignition switch the other just a blank plate). I still have some issues at high speed so I actually taped off half of the entry to the airbox. This helped a lot.

I have a k&N with a jet kit (not sure what size other than it isn't stock).

If you richen it up enough to take advantage of the high speed airflow you will have issues at full throttle opening at low speed.

When the CBR was new the hot trick was to drill a bunch of holes in the top of the airbox and richen up the jetting a lot and use a different needle. Gas mileage would drop I am sure and you would be running something that makes the bike less streetable.

KongBastard
 
  #8  
Old 06-18-2010, 08:13 AM
mrfisher's Avatar
Member
Thread Starter
Join Date: Mar 2008
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by KongBastard
I do not have fairings on my CBR. The problem is at high speed, not necessarily at full throttle. Turbulance plays a part as does air flow. This is a very common problem on the CBR.

I have sealed both of the holes in the frame (one side has my ignition switch the other just a blank plate). I still have some issues at high speed so I actually taped off half of the entry to the airbox. This helped a lot.

I have a k&N with a jet kit (not sure what size other than it isn't stock).

If you richen it up enough to take advantage of the high speed airflow you will have issues at full throttle opening at low speed.

When the CBR was new the hot trick was to drill a bunch of holes in the top of the airbox and richen up the jetting a lot and use a different needle. Gas mileage would drop I am sure and you would be running something that makes the bike less streetable.

KongBastard
Okay, this sounds like a plan. I have no desire at all to rejet this thing right now, I'm just using it to get back and forth to work on the freeway. I still actually have the upper cowl on the bike, so I think most of this is from turbulence around the frame holes. I think I'll try taping them party off today, and if that doesn't work, I may try to run tubing from them to somewhere up inside the cowl with quiescent air.
 
  #9  
Old 06-27-2010, 02:57 AM
xjoewhitex's Avatar
Senior Member
Join Date: Mar 2009
Location: Marietta, Ohio
Posts: 533
Likes: 0
Received 0 Likes on 0 Posts
Default

A friend and I have been working on a fighter for some time, and came into the same problem not using fairings. Leaving the intake tubes on and taping off the ram air completely did the trick. Any less and she shutters..
 
  #10  
Old 06-27-2010, 11:41 AM
mrfisher's Avatar
Member
Thread Starter
Join Date: Mar 2008
Posts: 41
Likes: 0
Received 0 Likes on 0 Posts
Default

What do you mean by taping off the air ram? Do you mean taping off the holes on the outside of the frame members where the tubes come out?
 


Quick Reply: Problems running without fairings



All times are GMT -5. The time now is 10:52 AM.