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In case I don't get around to working on the bike at all today here are some preview pictures of what I received from partsnmore.
First, I will comment on the overall experience with this business so far. Shipping costs did not seem too high or inflated. I never received a tracking number, so I was getting cranky and assuming my parts had not shipped. I ordered on a Friday and received my order the following Thursday; not bad, and better because it was a surprise.
The carb boots look great and appear correct in size.
The petcock I ordered looks to be of good quality and everything including the hardware appears highly resistant to corrosion. Extra fuel "nipples" (?!) were included.
The float needle and seat for my application did not fit. The picture might not show it well, but the Keyster part I received does not fit; it is small enough to just fall into the hole that a needle seat would normally screw in to. I have sent an email about this, as previously noted, and I will reserve any judgment until I get a response.
First, I will comment on the overall experience with this business so far. Shipping costs did not seem too high or inflated. I never received a tracking number, so I was getting cranky and assuming my parts had not shipped. I ordered on a Friday and received my order the following Thursday; not bad, and better because it was a surprise.
The carb boots look great and appear correct in size.
The petcock I ordered looks to be of good quality and everything including the hardware appears highly resistant to corrosion. Extra fuel "nipples" (?!) were included.
The float needle and seat for my application did not fit. The picture might not show it well, but the Keyster part I received does not fit; it is small enough to just fall into the hole that a needle seat would normally screw in to. I have sent an email about this, as previously noted, and I will reserve any judgment until I get a response.
Attachments
It's like deja vu- it looks like the stuff you got is exactly what I used and I am very pleased.
The large hole in the middle of the plate is threaded and the base of the petcock itself has a rubber o-ring gasket that you can probably see from the first set of photos above. The smaller screws on either side also have harder red gaskets provided which feel similar to some of the materials on gaskets found within the carburetor; specifically the float seat.
Edit:
As a side note I am not happy with the process of boiling my carbs in vinegar; it leaves a white crystalline deposit all over them. Since vinegar is an acid (and thus somewhat polar) carburetor cleaner does not take it off. Carb cleaner, from what I gleaned on the label, is largely made of non-polar solvents because it is designed to remove gasoline and oil which are non-polar. Ergo another solvent is needed; ether (starter fluid) or water works much better at removing it, but ultimately I am going to have to brush the crap off with pipe cleaners.
After drying, the operation of my butterfly valves and choke plunger was not smooth at all; some wd40 in the joints and on the moving parts seems to have completely fixed the problem. Mmm lube.
Edit 2:
Partsnmore got back to me in less than 24 hours. They state they don't know why the part doesn't fit because it is listed as applying to my model and year; they also issued me a return number. Does anyone else have a pre-1980 that has replaced the float needles and seats? Where did you get your parts? I have read somewhere that it is common for rebuild kits to contain parts that do not fit.
Edit:
As a side note I am not happy with the process of boiling my carbs in vinegar; it leaves a white crystalline deposit all over them. Since vinegar is an acid (and thus somewhat polar) carburetor cleaner does not take it off. Carb cleaner, from what I gleaned on the label, is largely made of non-polar solvents because it is designed to remove gasoline and oil which are non-polar. Ergo another solvent is needed; ether (starter fluid) or water works much better at removing it, but ultimately I am going to have to brush the crap off with pipe cleaners.
After drying, the operation of my butterfly valves and choke plunger was not smooth at all; some wd40 in the joints and on the moving parts seems to have completely fixed the problem. Mmm lube.
Edit 2:
Partsnmore got back to me in less than 24 hours. They state they don't know why the part doesn't fit because it is listed as applying to my model and year; they also issued me a return number. Does anyone else have a pre-1980 that has replaced the float needles and seats? Where did you get your parts? I have read somewhere that it is common for rebuild kits to contain parts that do not fit.
Last edited:
If you boil your carb I have been told you should remove the butterfly seals at the ends of the shafts. The boiling or using cleaners can hurt them and cause air leaks. If you want the right parts sometimes oem stuff (yamaha) is your best bet, or nos stuff on ebay.
Yeah, it was too late before I realized there was a rubber seal for the butterfly valves. I think they are fairly tough, however. The part I had to lube was the spring/bolt assembly attached to the throttle cable bracket. Vinegar is a weak acid and a little water probably won't do a lot of harm. I'll check for leaks with my bomb in a can (ether) once it is all together.
I took a break from studying for a bit to monkey with the bike and perform some diagnostics. The idle sounds OK, but when I transition from idle to 1/8th throttle or so I get bike-firing and popping from the right side only. The right side is also shooting flames when it backfires.
I got my trusty propane torch out and starting waving gas at different parts of the carbs and did not notice any change in rpm at idle; that's good!
When I put some gas in the right side intake I get a strong surge in rpms. When I put some gas in the left side there is no change in rpms. So, does this mean I am just running lean on the right side? Would running lean on 1 side upset the bike enough to cause it to stall out when the throttle is opened very slowly?
I am thinking that this is now a float height problem. Any ideas?
I went up 2 sizes already on the pilot jets (47.5) and mikesxs only has 1 size bigger (50). I have never heard of anyone having to increase the pilot jet so much. My air screws are closed (richer) which seems to help, but it is not enough. I also get a high idle (3000+ rpms) when choke is all the way out. The bike idles normally (1000 or so) when choke is back in.
I got my trusty propane torch out and starting waving gas at different parts of the carbs and did not notice any change in rpm at idle; that's good!
When I put some gas in the right side intake I get a strong surge in rpms. When I put some gas in the left side there is no change in rpms. So, does this mean I am just running lean on the right side? Would running lean on 1 side upset the bike enough to cause it to stall out when the throttle is opened very slowly?
I am thinking that this is now a float height problem. Any ideas?
I went up 2 sizes already on the pilot jets (47.5) and mikesxs only has 1 size bigger (50). I have never heard of anyone having to increase the pilot jet so much. My air screws are closed (richer) which seems to help, but it is not enough. I also get a high idle (3000+ rpms) when choke is all the way out. The bike idles normally (1000 or so) when choke is back in.
air screws? there is only a fuel mix screw at the front of the carb, undoing makes it richer.
undo it 3 turns amigo, and hope you have'nt over tightened it as the needle will snap off in the carb!
don't pull the choke out as much, its a 2 stage affair!
undo it 3 turns amigo, and hope you have'nt over tightened it as the needle will snap off in the carb!
don't pull the choke out as much, its a 2 stage affair!
That confuses me, because I've been told my several people that on the pre-1980 bikes closing it makes it richer. Gosh! I have been tightening and opening it by hand. When I have used a screw driver I go slow and stop when I feel any resistance. Last time I pulled them off they were intact. I'm going to go try opening them...
Ok, at 3-4 turns out, it seems to run nice from idle to slight throttle, but it wants to stay at high rpms now! It seems to like being at 3-4000. I have to blip the throttle to get it to come down. Could my main jet be too large? I did go up 3 sizes! 137.5 to 145! I do have 142.5's in the garage.
Drewps! She's running right; it was the floats!
I tried the smaller main jets and that made no difference, so I switched back to the bigger ones.
First, I was flooding a bit. Second, the small tabs that hold the floats against the mounting posts were both bent and not making contact like they should. These are the little tabs that prevent the floats from "falling" too low when they are right-side up. I bent the little tabs with pliers and adjusted the height to 26mm from below the gasket, or 24mm from the lip on the edge of the bowl.
It idles great and I can rev smoothly at very low rpms. So, I put my game face on and decided to try and ride it. Good thing I have a long driveway! I didn't dump it, but wow it took off fast. Are you supposed to ride the clutch a bit for a smooth take off? Even at low rpms the thing pulls hard.
I am sure I still need a synch, but I am content for now!
I tried the smaller main jets and that made no difference, so I switched back to the bigger ones.
First, I was flooding a bit. Second, the small tabs that hold the floats against the mounting posts were both bent and not making contact like they should. These are the little tabs that prevent the floats from "falling" too low when they are right-side up. I bent the little tabs with pliers and adjusted the height to 26mm from below the gasket, or 24mm from the lip on the edge of the bowl.
It idles great and I can rev smoothly at very low rpms. So, I put my game face on and decided to try and ride it. Good thing I have a long driveway! I didn't dump it, but wow it took off fast. Are you supposed to ride the clutch a bit for a smooth take off? Even at low rpms the thing pulls hard.
I am sure I still need a synch, but I am content for now!
ahale2772
XS400 Addict
bc, where is the adjustment for the float level? do you have to pull the bowls off each time?
Oh, yeah; I pulled the carbs off each time I made an adjustment. I can do it pretty fast now haha. You just have to bend the little "tang" that rests on the float needle. Just make sure you are holding the floats in your hand when you bend the tang and not pushing it against a table or something. There is a second tab on the floats that pushes against the right "tower" where the pin inserts. If this little tab bends and does not make contact with the "tower" you won't be able to measure or maintain a proper float height and they won't move the way they are supposed to. Mine were bent and I think that was my biggest problem. When the tab pushes against the "tower" it allowed the float to pivot properly off of the needle.
