cx'y 500
- Thread starter IED
- Start date
IED
Been Around the Block
This afternoon I had about as much of Christmas Telly as I could take, so I went down my shed and swapped the jets in my carbs.
This is the main jet the needle drops down into. The standard jet is a 112. This allows a fixed amount of fuel into the engine from the float bowl. This amount of fuel is directly connected by the amount of air the CX's air box allows into the carbs.
Because I have replaced the CX air box with Hi-flow filters this will upset the balance between the fuel/air mixture in the carbs, and the air to fuel ratio is now out of sink.
I have gone up one jet size to 115's as the hole in them is a tiny bit bigger it will let more fuel in to help restore the balance of mixture, and also produce a bigger bang resulting in a little more power.
Because of this the dB killer is now not as effective as it was and the bike is just a little more noisy than with the 112 jets.
As I've been rebuilding the bike I've been changing out as many of the old screws and bolts for stainless hex cap head screws as I can. They are so much easier to do up and undo than cross heads and look better too.
After I got the carbs back on I took it out for a short blast and the new jets really have woken up the carb's. I just need to do a bit more to the set-up, and balance the carbs, then book a slot on the Dyno to see if the changes I have made have had a positive effect on the motor.
As usual I'll be doing a write up on balancing the carbs at a later date, so if you are mildly interested keep an eye on this thread.
This is the main jet the needle drops down into. The standard jet is a 112. This allows a fixed amount of fuel into the engine from the float bowl. This amount of fuel is directly connected by the amount of air the CX's air box allows into the carbs.
Because I have replaced the CX air box with Hi-flow filters this will upset the balance between the fuel/air mixture in the carbs, and the air to fuel ratio is now out of sink.
I have gone up one jet size to 115's as the hole in them is a tiny bit bigger it will let more fuel in to help restore the balance of mixture, and also produce a bigger bang resulting in a little more power.
Because of this the dB killer is now not as effective as it was and the bike is just a little more noisy than with the 112 jets.
As I've been rebuilding the bike I've been changing out as many of the old screws and bolts for stainless hex cap head screws as I can. They are so much easier to do up and undo than cross heads and look better too.
After I got the carbs back on I took it out for a short blast and the new jets really have woken up the carb's. I just need to do a bit more to the set-up, and balance the carbs, then book a slot on the Dyno to see if the changes I have made have had a positive effect on the motor.
As usual I'll be doing a write up on balancing the carbs at a later date, so if you are mildly interested keep an eye on this thread.
IED
Been Around the Block
Following day when the engin was cold I tried to start it again and all it would do was cough and bang.
I changed out the 75/115's for a 90/120 jet setup and it now works great with my filter/zorst. I also made 2 x 1mm thick shims from ptfe plastic and fitted one on each needel. Next I'm going to balance the carbs and it will be ready to go on the dyno. ;D
I changed out the 75/115's for a 90/120 jet setup and it now works great with my filter/zorst. I also made 2 x 1mm thick shims from ptfe plastic and fitted one on each needel. Next I'm going to balance the carbs and it will be ready to go on the dyno. ;D
crazypj
Split personality, I fake being smart
So that's where I originally got 112 mains ???
Haven't done CX carbs since around 1980, had 2 spare jets but not a clue where they came from until I saw your post about swapping to 115 (came in sets of 4)
Looking good. 8)
Has 'plod' got more lenient on number plates?
We used to have a hell of a time with anything not BSI stamped, and exactly to spec (so I got a copy of 'Construction and Use' and stuck to the letter of the law, much smaller plate than po-po thought was 'legal' ;D )
Haven't done CX carbs since around 1980, had 2 spare jets but not a clue where they came from until I saw your post about swapping to 115 (came in sets of 4)
Looking good. 8)
Has 'plod' got more lenient on number plates?
We used to have a hell of a time with anything not BSI stamped, and exactly to spec (so I got a copy of 'Construction and Use' and stuck to the letter of the law, much smaller plate than po-po thought was 'legal' ;D )
IED
Been Around the Block
I really enjoy the build, and I've taken it out a couple of times and had some fun on it so its time to think about the next project. Plus I'll never sell my Blade, and I have some upgrades in mind for that. I just brought a 240/40-18 tyre from America that I'm going to put on an 18" Honda civic car wheel. 8)
