rides fine for a while then the sound in the muffler changes from sports bike to chopper or harly sound and wants to turn off as im rolling .. then i come to a complete stop it shuts off .. i try to turn it on and it has trouble so i lift the tank and it seems to turn on and sometime i have to put the choke all the way for it to turn on even after its warm .. any ideasto this couse ? dirty carbs?

 

You may have a blocked breather tube on the fuel tank, when it happens again just open the fuel tank cap and listen for air rushing in. It may be hard to start on re-start due to fuel having to fill the bowls in the carb again, it also helps others to diagnose your probs if you say what year you have as early models run a fuel pump where later models did not.

 

merged back in here with original problem with related discussions - no need for
duplicating threads on same issue

 

ive have bin doing some thinking and reading and was wondering if my issue with the bike had anything to do with the air breathers i have on the carbs .. each carb has a air breather and also a 5th air breather that would connect to the air box . instead of telling my issues i was wondering if u can TELL me the issues i would have with this set up.. to my knowledage this is the only othere mod othere than the gravity feed it has do to the previous owner

 

Can you take a pic and post ?

 

yesssss ! i just found out how to upload so u guys can see . have to note i worked on the bike and found a slite leak of gas on the universal filter and snapped the plastic .. good thing i went to the dealer and got the OEM gas filter and took it for a 30 min test run as thats about the time it starts to act up.. ran fine 0_o . will take a longer ride tomorrow to confirm if it was the universal filter .. happen to notice that the universal (3/8)was slitely smaller than the OEM one witch im not sure of the size but it seemed to let the gas flow in smoother than the universal ... maybe it was that stupid filter ???? ill post pics and more info tomorrow

 

cool well I just got an 87 myself a few days ago and ripped out the filter and pump
assembly and ran the line direct to the carbs ---- after 3 years of sitting the bike
fired up after about 5 minutes (drained and rinsed the tank out before of course)

So you can run MK1 bikes with gravity feed and no filters - but filters are always a
good idea anyhow - I'll probably splice one back in not going to bother with the
pump though - unnecessary and just another electric component to fail eventually.

That's great you figured it out man well done

If it still acts up maybe try it without the fuel pump

 

Hey:

The MK1 87-88 STD fuel line size is 5/16" ID and 5/16" ID fuel filter which is smaller than 3/8" when removing the electric fuel pump you go up in size to 3/8" ID line and filter.
Also the air cleaner pods cause some issues if not jetted just right, but mostly on the top end. They take some fiddling with to get them to run well thru the complete range and may need staggered jetting so if you do take off the carbs and find mismatched jet sizes do NOT be too worried if your plugs are burning correctly. Good Luck with your bike and hope you found your problem. Welcome to the wonderful CBR1KF world, it's a great place to be.

Dub

 

well im running it with out a fuel pump Sprock , but cbr1988 wrot something very interesting about the fuel line ... im currently running a 5/8 fuel line straight to the petcock clamped on witch is connect to the fuel filter and from there to wear the "T" splits the gas into the carbs .. am i flooding it?? the 5/8 line seems to fit with better ease than my first attempt with the 5/16 line on the petcock witch took me forever to try and fit on..again pics will be up tomorrow

 

failed to mention i also filled her up today and my fuel meter worked !? seems to not read when low on fuel .. also goin back to the fuel line .. could my bigger lines be the reason y she sucking gas like a dragon?