[poffypoffa]

Just want to get my ducks in a row. I've been reading the various websites dedicated to the issue, and I've read through my Haynes manual. I have my right-angle screwdriver ready to go, and I'll have the replacement carb screw set. As far as I can tell:

.5) turn off the fuel petcock
1) Loosen the bolt to drain the gas out of the float bowl
2) Remove the four screws that hold on the float bowl cover
3) remove the main jet (while using a wrench to keep the needle jet holder from falling out)
4) install the replacement main jet
5) remove the pilot jet
6) install the replacement pilot jet
7) replace the float bowl cover
8) turn back on the fuel
9) fire her up!

The Haynes manual says I need to replace the gasket--is that really necessary? Also, which of the connectors (electrical or otherwise) must I remove before rejetting?

Thanks!

 

[sweatmachine]

I've rejetted a few times and never replaced any gaskets, no fuel leaks to date (14,000 miles).

Just yank loose all the wires hanging from the carbs, 2 wires per side, and reconnect accordingly.

 

[sweatmachine]

you'll probably want to mess with the needles too, to get to those you have to remove (or lift the rear of) the gas tank.

then you can access them through the top of the carbs, pull the tops off, then remove the spring and the little white plastic spring holder thingy, then you can reach down inside the slides with a needle nose and pull the needles out the top to either install Thruxton needles (with or without shims) or install shims on your needles.

Playing with needles can make a big difference.

don't do drugs kids.

 

[poffypoffa]

Oh, I agree, but I'm going to let my shop replace the needle jets--I have the replacements. The shop has to replace a bum cam cover, anyway. I just want to avoid running the engine too hot in the meantime, so I figured I could do the jets myself, when I do the pipes.

[ This message was edited by: poffypoffa on 2006-11-07 17:43 ]

 

[POPPE]

If you do replace or mess with your needles take the rubber diaphrams out and let them sit in the freezer for awhile its less frustrating to put them back,or get yourself a feeler gauge you'll need it.

 

[merlin]

An inspection mirror will help alot locating the jets. Keep a carb diagram handy too.

 

[poffypoffa]

Can't I just lie down under the bottom of the carbs and look up at them? That's what I assumed I would do.

 

[Guest]

not sure

 

[Pict]

FIRST thing to do is disconnect / remove battery.

You are draining the float bowls, the seat is off cos you removed the fuel tank, you lay your screwdriver down, it shorts the battery, there is a spark.............

 

[SpeedyPete]

On 2006-11-07 17:10, sweatmachine wrote:
you'll probably want to mess with the needles too, to get to those you have to remove (or lift the rear of) the gas tank.

Playing with needles can make a big difference.

Yes and no.

Yes you may want to mess with the needles but give a ride with the new jets first. One thing at a time.

No you don't need to remove the tank to get at the needles - the diaphrams can be easily accessed once you get the caps off. I did it anyway. Think about doing this yourself - its actually easier than swapping the jets.

In my experience, going to the thrux needles made a small but important difference.

 

[sweatmachine]

you don't have to take the diaphragms off to change needles, you can reach down in there with a pair of needle nose (get it?) and not have to mess with the GD diaphragms....

but you have to remove the tank, or lift it. I hate putting the diaphragms back in, and I can take off the tank and reinstall it in less than 10 minutes...

 

[sweatmachine]

and yes you can lay on your back to see, probably won't have to do more than sit on the ground.

if you haven't seen dinqua's site, go to it!

Dinqua!

this page will help

dinqua's carb picture CLICK!

 

[boboso]

All good advice from everyone (disconnect battery - good tip!).

I also recommend being very careful with the carb screws on both the float bowls as well as the top screws. These can easily be stipped and can cause real problems if damaged (plus the carb metal is soft). Mine were pretty tight as delivered from the dealer, but I knew ahead of time to be careful and use steady pressure. Once off, I replaced with a hex/allen set from "one of our fine advertisers".

On my Thruxton I have to remove the tank as I am not so flexible. Better for me as it allows me to inspect or work on the other areas (cleaning, hose routing etc).

 

[rwright]

I don't want to start disinformation but...isn't there the possibility that the floats and float needle could fall out if done while on the bike? Step 0.75 - place a towel over the engine case to catch any drips (or parts that may try to get away).

Rich

 

[sweatmachine]

I guess it's possible, but I've never had anything fall out.

 

[badrufus]

1. I've messed with my jetting several times and have never replaced the float bowl gaskets. I have been careful with them and given them a look to make sure they were installed correctly;
2. Things can fall out, but I've not had a problem with that either. A clean drop cloth under the bike will help to stop things from rolling away;
3. The jets are more work than the needles, but both are quite doable if you check out dinqua's site and the Haynes manual. For some reason, I've never had a problem with the diaphrams. Usually, if someone can have a problem with something, I do;
4. The biggest challenge is getting the float bowls off, especially on the LH side where the idle speed knob is in the way. The problem is the d*@m phillips head screws. Since you will probably strip 2-3 screws in the process of removing them, have the newbonneville.com replacement allen head screw set at hand before you do this job. Once you replace the stupid phillips head screws with allen heads, future float bowl removal is much easier;
5. If you haven't already, check the Jenk's site for excellent tuning info
Jenk's
6. Once you've figured out how to rejet and get to the needles, the next challenge is carb synchronization, a pretty important topic for the Bonnies.

Have fun!

 

[Anchorbend]

I found the easiest way to get the needles out is using a flexible claw tool. Press the button on the top, opening up the claw a little, releasy and pull the needle out. I think I got mine for a couple of bucks. Autozone etc. carry them.

 

[meatwagon]

Wow I never thought of that claw tool. I use an 8 inch pair of hemostats,slightly bent.No tank removal .The needles are aluminun or something non magnetic so you must grab them.Shims usually are steel,so if one falls off the needle you can use a telescopic pencil type magnet to fish it out of the carb.Be careful to grab only the needle when you grab,it's easy to get the holder at the same time,you can tell when you are pulling to much out of the carb. Don't mess with the diafragm at all .

 

[SpeedyPete]

On 2006-11-08 09:42, boboso wrote:
All good advice from everyone (disconnect battery - good tip!).

What, and take all the excitement out of it????

P

 

[panthercity]

On 2006-11-08 11:43, rwright wrote:
I don't want to start disinformation but...isn't there the possibility that the floats and float needle could fall out if done while on the bike?

Only if the float pivot pin is removed.