Taking the carb plunge....

[don07tncav]

Got my Claimers, printed off the long how too thread, got the rebuild kits, now for the attempt.

My number three cylender has little to no gas getting to the plug so I feel I've got to do the deed.

Sea foam made a huge difference on the other carbs but the number three just won't clear out.

Just what are those little brass thingies in those kets!!???!!!

[John]

Probably one of the best pieces of advice would be to disassemble and reassemble just one or two carbs at a time. That way there can be less chance of mixing of parts, and you always have a complete carb as a reference. Don't be afraid of them, they are very easy to take apart and put back together.

[ratbyk]

Carb Rebuild

Don, a word of caution on the rebuild kits. The jets supplied in the kits even though they may have the same number stamped on them as the original carburetor jets are not always (some times never) the same size. The original equipment Mikuni jet sizes and numbers do not match the after market jets sizes and numbers. In particular, the pilot jets supplied are usually away too big in comparison to the original Mikuni's.
Do a visual comparison or even better, a drill bit comparison between the originals and the after market. If the jets supplied in the kits appear to have a larger hole than original, DO NOT USE THEM. If you do you will be taking them apart again to switch them back.
Brass jets really do not wear. The only time the "flow rate" hole gets enlarged or worn is if someone tries to "ream" them out.
Do not soak the carburetor bodies in carburetor cleaner. There are rubber seals in/on the throttle shafts that will be destroyed by strong carb cleaners.
Do one carb at a time as suggested. Spend extra effort cleaning out the various ports/channels/drilling's in the main bodies. This is where you will correct your low "flow" problems.
Ken/Sooke
78E Ratbyk
82 FT500 "lilRat"
92 ZX11 Temptress

[Hobbit]

jets

Don, I used the jets that came with one of the aftermarket rebuild kits and had exactly what Ken mentioned, a way to rich condition.
I ended up having to play with the floot levels and metering rods to get the bike to run correctly.

[don07tncav]

Thanks for the quick replies gents. I'll follow your advice and do one at a time. Quite frankly, I thought of doing just number three since there is a problem and skip the rest for now.

After reading the Clymer's I realised the piece was the jet.

[nashville_bill]

If you have a problem, I'm only a couple of hours away. Do you have a way to sync the carbs after the rebuild?

[UncleSpot]

Don,
you wrote, "After reading the Clymer's I realised the piece was the jet."
I must be blind... and I read the carb section 3 or 4 times...
I just got a complete set of carbs - to rebuild, and then do a 'one-day' swap, so I'm not down too long...

Another question for the group: if you go to another exhaust system, more exh.flow, the jets have to be bigger(?)
I'll be doing the new carbs, and exhaust the end of January and 'don't like to do things 2 or 3 times... besides; it cuts into 'riding time'

[don07tncav]

No Bill, I planned to do the wire in the butterfly trick until I could get one done either through Yamaha or a area, (There ain't no local guys out here!), repair guy who works on bikes. I also hated to take up a day of your time doing something like this that I need to learn how to do myself anyways!!!

Spot, I thought about doing the same thing but no carb sets for an 81 have gone through e-bay since I bought the bike. The rebuild kits I picked up have these brass jets in them as a part of the kit.

[sixtysix]

I suggest you get a set of screwdrivers with flat (non-tapered ends) for carb work. Mine are PB Baumann brand and according to the specs are: Screwdrivers for slotted screws, parallel tip according to VSM standard 35 601.They are Swiss made, and they work great for gunsmithing as well. You don't want to burr up the jets.



I only use them for carb work and nothing else.

[nashville_bill]

I modified a couple of screwdrivers that I only use for the jets in my carbs with non tapered tips and exactly the right thickness and width. I guess I'm more of a shade tree mechanic than Gary is.