So I just got my bike up and running after giving the carbs a nice clean. However, there is obviously some adjustments that need to be made. Whenever I hit the gas the revs drop a little then go way up and stay up for a while. The throttle is EXTREMELY laggy (in other words). What's the deal? Any ideas? It sounds like it's way too rich to me, but I'm a newbie at this
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Bike Acting Strange
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- adjustment lean rich tune
It depends on the floats. My earlier '78 runs perfect at 26mm with brass floats.
Your "lower" float height could be the issue, yep.
The "lower" the float height the "later" the float needle closes when the bowls fill up (it's hard to visualize). If the fuel level gets too high you can get major or minor flooding. The rpms dropping and the delay makes me think you're too rich as well.
Your "lower" float height could be the issue, yep.
The "lower" the float height the "later" the float needle closes when the bowls fill up (it's hard to visualize). If the fuel level gets too high you can get major or minor flooding. The rpms dropping and the delay makes me think you're too rich as well.
carbs will make all the difference.
Since your bike is an 81 it probably uses brass floats which the measurement is correct at 26 mm.
Also take the carbs apart completely remove all rubber/plastic parts and boil them using simple green or lemon juice.
After putting them back together do a search on how to properly sync your carbs,there a bundle how to do in the lounge section that covers this.
Did you rejet after adding the unipod filters?This usaly requires an increase main and pilot jets.
Happy cleaning.
Also take the carbs apart completely remove all rubber/plastic parts and boil them using simple green or lemon juice.
After putting them back together do a search on how to properly sync your carbs,there a bundle how to do in the lounge section that covers this.
Did you rejet after adding the unipod filters?This usaly requires an increase main and pilot jets.
Happy cleaning.
Yes clean the carbs manually, that will probably fix your problems. Open them up and be careful not to break anything (there's brass parts there, they're relatively soft). Pay special attention to small passages and poke through those with something very thin (super thin wire or something). Set the float height and write down which size jets you have in there.
Put it all back together and report back.
Put it all back together and report back.
Tombo
XS400 Addict
OP - definitely time for cleaning number two. You definitely need to take them apart. If you go with compressed air, carb cleaner and wire guage brushes (my personal technique), you well manually clean every passage, remove each jet and clean it's passages. You can keep the butterflies attached for thus technique. If you want to boil the carbs, you will need to remove butterflies in order to protect butterflyy shaft seal. I don't like this because butterfly bolts are easy to strip.
When cleaning jets, the needle jet is always a place you will find the biggest change after getting right. There is the needle (male) and the jet (female). Remove the female portion, and notice that it has a bunch of tiny holes on the sides. This is where a write guage cleaner is the best thing ever. These tools are a collection of wire guage needle dudes that have ribs on them, so you can use them to de scale the holes. My holes went from almost opaque to being able to see straight through the opposing hole, and see the world upside down through the other side like an aperture.
Yeah, get ready to spend at least on hour on the cleaning (not including disassembly or reassembly.
Cheers!
When cleaning jets, the needle jet is always a place you will find the biggest change after getting right. There is the needle (male) and the jet (female). Remove the female portion, and notice that it has a bunch of tiny holes on the sides. This is where a write guage cleaner is the best thing ever. These tools are a collection of wire guage needle dudes that have ribs on them, so you can use them to de scale the holes. My holes went from almost opaque to being able to see straight through the opposing hole, and see the world upside down through the other side like an aperture.
Yeah, get ready to spend at least on hour on the cleaning (not including disassembly or reassembly.
Cheers!
BamaBill
XS400 Addict
jets are cheap from MikesXS, just go ahead and order carb rebuild kits, new float needle assembly, if you are running air pods go ahead and order the #45 pilot jets and get several size main jets 137.5/140/142.5, that will give you some room to play with the jetting btw, your stock size is 135. Go ahead and get new air mixture screws also, you will be glad you did later on.
BamaBill
XS400 Addict
Just to have several choices to play with I would go with the next 3 sizes up. Not every bike responds the same, but I'm running stock air filters(no boxes over them), shorty emgo mufflers and I'm running #45 pilots, and 140 mains, stock needle, and air adjustment screw is out 2.25 turns.
