Help! My bike won't run right!!!

[budsutten1]

Thank you so much! I will do that!! I did check the intake boots, and they are good, and the throttle cable is good also, but I never thought about the oil thing. Never even heard of that, and I haven't changed the oil in a decent while! I will also let you know what I find out! Thanks again!

Bud

[windjammergump]

air cleaner

make sure air cleaner and oil are clean and fresh.....if you running an airbox cant tell you about pods ...i have no experience running these....i have a low end fuel problem myself .....i have read on here ...clean and sync..three times are the charm....drag bikes have to put on run and try and remove about 3 times also.....good luck as i need it myself

[LoHo]

Do the sunlight test on the diaphragms. If there is a pin-hole in one of them, it keeps the idle down until the vacuum is enough to lift the needle, then drops back down as the vacuum levels off, then back up, and so forth, resulting in idle-VROOM!-idle-VROOM!-idle-VROOM!....

[cywelchjr]

Uhh, no. . . The diaphragms don't to any lifting till you start to transition to the mains, there's not enough air flow creating enough vacuum to make them move before then. Just watch them without filters in place at idle sometime, you will see them sit dead still at idle. They WILL however cause the bike to bog during and after transition as they won't raise as far as their supposed to.

I've worked on more than a couple of CV carbs and never seen a set of slides move at idle, and they won't move much even as you rev it into the higher ranges without any load, it still doesn't create enough air flow to do much without a load.

[xs11lover]

I'm not sure if this will help at all....but are the vacume lines hooked to the right ports...mine got switched around or one popped off one time and it acted that way. I would tend to think if you had the carbs apart the answer would be in the carbs, but what do I know.
"life is what happens while you're messing with your carbs"

[LoHo]

Also, your vacuum plugs might be dry and brittle and creating a vacuum leak.

CJ, I understand that the diaphragms are not supposed to have anything to do with idle, but early on in my XS experience I had those symptoms. The synch would sort of balance the four cylinders, but two had several tiny holes in the diaphragms. If I touched the throttle, the increased vac would open all four wide open and the engine would scream. When I repaired the holes, my "synch" was way off, but the new synch stuck.

[geobiker]

cable routing

I know that cable routing was mentioned. Did you check to make sure that the throttle cable linkage on the carb body isn't touching a clamp on a carb manifold boot. One time (of the many) that I reinstalled the carbs on my 1100, when i tightened the clamp it shifted just enough so that the thottle cable linkage touched it and I had similar symptoms to the ones you describe. JOT.

[Shawnb]

xs850

fuel has definitly be getting into the combustion chamber from the fuel tank, Your carbs must be allowing fuel to come through one are more carbs at an small unusaul rate. which means you need to adjust your carbs in someway.

[DenyP]

Did you get her running? A great source of info and help for these bikes is available at http://www.yamaha-triples.org.
Really great coverage with photos dealing with Hitachi carbs.

Deny