studricho
04-05-2008, 12:50 AM
I thought I'd post this up here aswell. You never know hen this may come in handy. (Yes, It's posted on the cbr250.forum site too)
I've been wanting to do this for a while and here it is.
Warning! This is not an easy task and perform at your own risk! This thread is a guide to help people with some mechanical knowledge.
Now that's out of the way. First let's assume that your carbies are out and one the bench. I prefer to leave the fuel bowls on, less chance of you breaking something.
http://img525.imageshack.us/img525/9766/dscf2960vb6.jpg
First gently bend the 16 gold tabs just enough to clear the screw. If they feel like it's going to snap, then break them off and throw it away. You don't want them to snap and get sucked into the engine.
Next undo the 16 screws and remove the plastic base. These screws are tight and have loctite on them, so use a quality screw driver or even an impact driver.
http://img169.imageshack.us/img169/6205/dscf2963lt2.jpg
This is what it will look like. (Yes, different carbies)
http://img329.imageshack.us/img329/4821/dscf2965va5.jpg
Next flip the carbies over and remove the single bolt from every fuel bowl. Spray some WD40 into the holes. This will help you later on, trust me. (I know the bowls are on wrong, spare stuffed carbies)
http://img262.imageshack.us/img262/166/dscf2971ry5.jpg
Now to remove the choke rail. Remove the 2 screws and pay careful attention on how it goes together. I've included some detail pictures of the return spring/plastic locater and the holding screws/plastic washers.Check the operation of the choke.
It should slide back and forth with no binding. Many cbr's have bent choke rails causing the choke rail not to slide all the way across.
http://img294.imageshack.us/img294/4765/dscf2973hq2.jpg
Here's a close up of the return spring and plastic locater. Take note how this all fits in.
http://img186.imageshack.us/img186/9620/dscf2975yw7.jpg
And here's one of the holding screw and plastic washers. The stepped washer goes on the carby with the narrow part facing up. This is what the choke rail runs on. The normal plastic washer fits neatly over the stepped washer once the choke rail is back on.
Some WD40 upon assembly will help with the smooth operation of the choke.
http://img113.imageshack.us/img113/6498/dscf2976go6.jpg
The next part is fun. You need to remove the balance spring between carby 2 and 3. You can see it here. It's the one below the screw.
This picture was taking by holding the throttle open and the screw hasn't been touched in this picture.
http://img261.imageshack.us/img261/7277/dscf2980xg8.jpg
That's the screw in there at the end of the screwdriver.
I suggest you turn the screw all the way counting how many turns and write it down. Then back off the screw until it's flush with the plate. That will make removal of the spring easier.
http://img232.imageshack.us/img232/8564/dscf2967ny7.jpg
Now we need to remove both the long bolts that hold these puppies together. You can see the 8mm nut and the 10 mm nut. By spraying WD40 earlier it would have penetrated the 8mm bolt and making it easier to remove. You may have to gently tap these bolts out.
http://img371.imageshack.us/img371/8413/dscf2969lf1.jpg
I told you that these bolts are long. Remove them completely out. When you reinstall them, make sure you have even thread on both ends.
Once these bolts are out your carbies may fall apart. Depending on the age and condition of the bike. If it feels like it's going to fall apart in your hands, then do yourself a favour and cable tie carby 1 and 2 and 3 and 4 together. We only want to split 2 and 3 carby.
http://img181.imageshack.us/img181/8140/dscf2982wl8.jpg
I told you this is not for the faint hearted. You actually need to split the bank in 2 to get to these o-rings. You can now see why we had to remove that spring on the balance screw.
Reassembling in reverse. Just pay careful attention to the dowels, rubber seals, T-piece and the choke cable holder (It can go on the wrong way).
You should be able to gently tap the carbies back together.
Do not use bolts to pull the carbies together! If they won't fit together, you have something not lined up.
I will not be held responsible for your breaking your carbies or loosing springs. Please use a bench area, don't do this on the lawn.
Now that's all done make sure you put the balance spring back in and turn the screw all the way in and then out to where it was before.
You will need to balance the carbies after this. Please use rubber grease/vasoline to install the new o-rings.
I've been wanting to do this for a while and here it is.
Warning! This is not an easy task and perform at your own risk! This thread is a guide to help people with some mechanical knowledge.
Now that's out of the way. First let's assume that your carbies are out and one the bench. I prefer to leave the fuel bowls on, less chance of you breaking something.
http://img525.imageshack.us/img525/9766/dscf2960vb6.jpg
First gently bend the 16 gold tabs just enough to clear the screw. If they feel like it's going to snap, then break them off and throw it away. You don't want them to snap and get sucked into the engine.
Next undo the 16 screws and remove the plastic base. These screws are tight and have loctite on them, so use a quality screw driver or even an impact driver.
http://img169.imageshack.us/img169/6205/dscf2963lt2.jpg
This is what it will look like. (Yes, different carbies)
http://img329.imageshack.us/img329/4821/dscf2965va5.jpg
Next flip the carbies over and remove the single bolt from every fuel bowl. Spray some WD40 into the holes. This will help you later on, trust me. (I know the bowls are on wrong, spare stuffed carbies)
http://img262.imageshack.us/img262/166/dscf2971ry5.jpg
Now to remove the choke rail. Remove the 2 screws and pay careful attention on how it goes together. I've included some detail pictures of the return spring/plastic locater and the holding screws/plastic washers.Check the operation of the choke.
It should slide back and forth with no binding. Many cbr's have bent choke rails causing the choke rail not to slide all the way across.
http://img294.imageshack.us/img294/4765/dscf2973hq2.jpg
Here's a close up of the return spring and plastic locater. Take note how this all fits in.
http://img186.imageshack.us/img186/9620/dscf2975yw7.jpg
And here's one of the holding screw and plastic washers. The stepped washer goes on the carby with the narrow part facing up. This is what the choke rail runs on. The normal plastic washer fits neatly over the stepped washer once the choke rail is back on.
Some WD40 upon assembly will help with the smooth operation of the choke.
http://img113.imageshack.us/img113/6498/dscf2976go6.jpg
The next part is fun. You need to remove the balance spring between carby 2 and 3. You can see it here. It's the one below the screw.
This picture was taking by holding the throttle open and the screw hasn't been touched in this picture.
http://img261.imageshack.us/img261/7277/dscf2980xg8.jpg
That's the screw in there at the end of the screwdriver.
I suggest you turn the screw all the way counting how many turns and write it down. Then back off the screw until it's flush with the plate. That will make removal of the spring easier.
http://img232.imageshack.us/img232/8564/dscf2967ny7.jpg
Now we need to remove both the long bolts that hold these puppies together. You can see the 8mm nut and the 10 mm nut. By spraying WD40 earlier it would have penetrated the 8mm bolt and making it easier to remove. You may have to gently tap these bolts out.
http://img371.imageshack.us/img371/8413/dscf2969lf1.jpg
I told you that these bolts are long. Remove them completely out. When you reinstall them, make sure you have even thread on both ends.
Once these bolts are out your carbies may fall apart. Depending on the age and condition of the bike. If it feels like it's going to fall apart in your hands, then do yourself a favour and cable tie carby 1 and 2 and 3 and 4 together. We only want to split 2 and 3 carby.
http://img181.imageshack.us/img181/8140/dscf2982wl8.jpg
I told you this is not for the faint hearted. You actually need to split the bank in 2 to get to these o-rings. You can now see why we had to remove that spring on the balance screw.
Reassembling in reverse. Just pay careful attention to the dowels, rubber seals, T-piece and the choke cable holder (It can go on the wrong way).
You should be able to gently tap the carbies back together.
Do not use bolts to pull the carbies together! If they won't fit together, you have something not lined up.
I will not be held responsible for your breaking your carbies or loosing springs. Please use a bench area, don't do this on the lawn.
Now that's all done make sure you put the balance spring back in and turn the screw all the way in and then out to where it was before.
You will need to balance the carbies after this. Please use rubber grease/vasoline to install the new o-rings.