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Discussion Starter #1
Hi guys.
Soo i have been lurking these forums for a while now and thought i would introduce myself and my bike :eek:
I have a 1991 CBR250RR, had her for a bit over 8 months now. Been using this forum as my main go to guide when it comes to maintaining the bike.

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Anyway!

The bike has been running a little rough and decided it was time to do the dreaded carb clean, and thank god i did! The amount of gunk and crud inside was disgusting. I noticed the carb boots where as hard as rocks and had cracks all through them, so i decided it was probably time to the replace them.
Ordered a set from RB as advised in another thread, they should be here tomorrow.


Problem is... i cant get the old ones off! i have tried using the hair dryer to make them a little softer and easier to work with but its simply not moving.
Any ideas would be greatly appreciated :)
 

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Since your replacing them, then use a stanley knife and cut them off :)

There'll be a fair bit of gunk on the inside of them getting all crusty etc.

You'll need your carbies balanced once you put it back on.
 

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Discussion Starter #4
Welcome,

Guess I have to ask, did you unscrew what holds the carb boots to the ports?
Yeah i should have added that the carbs are off the engine and the boots are currently connected to the carbs.

Ill have a go at them with a stanley knife and see how that goes!

Also i did a little search but haven't found much on carb balancing, is it a difficult procedure on this bike?
 

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Sounds like you've in screwed the wrong clamps. It would be much easier to take them off the boots still attached to the ports. If you take all the clamps off you should just be able to pull them off. If not you can still use a Stanley knife as stated above. I'm new to bikes but purchased a Morgan carbtune pro and I found it to be quite simple after doing both my bikes. Depends how you are with those kind of things. As I see it and everyone says these bikes are all about learning.
 

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Discussion Starter #6
Yeah i think i just unscrewed all the clamps to get it off the engine, was a real pain getting it out, with that said what would the smartest way be to put the new boots on, mount to ports and than slide carbs ontop? or other way around?
 

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Boots to engine, carbs to boots
 

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Heat gun or hair dryer, heat them up real good, get screw driver and pry them off :)
 

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yeah, since you've got replacements just go to town on them with a big set of plyers/sharp stanley knife.

Hell if you really cant get them off just dissassemble the carb (take ALL the rubber bits out) and just burn them off with a butane torch, then sand the carbs clean again. That's really a last resort option though.
 

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Discussion Starter #11 (Edited)
Ok so bit of a status update.

Boots arrived this morning from RB racing :)
went to town as advised above on old boots, removed and cleaned rubber grime etc from carb boot location. (not really sure of the correct terminology there)
Mounted the new boots with a little rubber grease, couldn't believe how easy it was to get them on after mucking around with the old ones :eek:

i have the bottom clamps secured onto the boots for the engine side and now i'm looking at the clamps for the carb side. i have no idea how to get at them!
when i removed the carbs i undid the engine side clamps and just removed the carbs and boots all in one go.

here are some most likely less than useful pictures to help explain my situation :eek:
IMG_0080.jpg
IMG_0081.jpg

Everyone's advice has made everything a lot easier so i thank you for that!
 

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Long screwdriver make easy work, kimosabe.
 

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Put the carb boots on the carbs first then install them on engine, not engine first then carbs cause your gonna have a hell of a time trying to tighten those top screws on carb boots whilst carbs are on

carb boots on carbs first
 

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Exactly, put em on the carbs then install carbs on the bike. You'll need a long handled Phillips head to do them up. The oval cut out if the frame on either side is your purpose made access point.
 

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a 400mm long phillips head screwdriver is a must have for this type of work.

i find it easier to put the carbs on the engine first, then you can align the top clamps in such a way that they are accesable from outside the frame. slot the back edge of the carb into the boot and then rock them forwards with pressure against the front side of the carbs (if that makes sense). you should feel them "pop" as they go in. shine a torch through the gaps in the frame to make sure they are seated correctly and then do up the clamps.
 

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I must be the only backwards person on here then :D
 

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All of these tips PLUS put a little rubber grease around each end - attached to carbs first, then you can slide them on the engine.

Next time you come to take them off for a carb clean they will slide of easy and your knuckles will thank you.
 

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Discussion Starter #18
Thanks for all the advice, in the end i put the boots on the carbs then onto the engine and it was a breeze. The carb clean however did not resolve the issue i was having from the start :(

Ill start a fresh thread as its somewhat unrelated to carb boots.

P.S. Yes i do plan to balance the carbs :eek:

Edit: I might do some research around the forums before i post another thread
 

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You haven't balanced your carbs yet though? Carbs won't perform well if you only do 1/2 the job. You need to balance them. Make a manometer from some vinyl tube and two-stroke oil, balance them, THEN see if it's not the carbs.

+ are you sure there aren't any air leaks?
 
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