billyt

Cope You know fine well who wrote the article on the carbs/floats. You are just picking a fight. I will not get drawn into a discussion around floats moving up/ down once a bike has landed abruptly of a jump/rock. I have all the proof I need given to me by my mikuni factory training and through simple science. Bikes are not always parallel to the ground once they land and the fuel can and will slosh either forward or backwards in the float bowl causing a void and thus the floats will move down accordingly. If floats have no weight then why use a float? The fuel level goes down the floats go down. The fuel goes up the floats go, density yes but also due to their weight. If the bike landed perfectly square then the gas would not really go anywhere but just slightly compress thus no movement of the floats. BUT this is not reality, the bike usually lands front wheel first or back wheel first throwing the gas to one side or the other of the float bowl and the floats re-acting accordingly. This is the very reason there are two sets of adjustments on the brass tangs. One to control the travel up and one to control the travel down trying to isolate them somewhat from the movement of the fuel. I wrote a post a while back asking you to be honest with the members on this forum in the fact that you don't actually ride trials and have not been at an event or out practicing for around ten or so years yet you speak like you know all the latest about the bikes. I doubt you have actually seen a trials bike newer than 2003. I still keep in contact with many riders in the NTTA and they have not seen you riding ANYWHERE....... All one needs to do is to log onto the NTTA (North Texas Trials Association) web site and check the results going back for many years. See if Marks name shows up even once! You are Bench or magazine trials rider............ period. Bring it on. Or bury the hatchet.

I re-posted old article here below Mikuni Carb Setup By Billy Traynor 
The first area of urban legend is the two little brass outlets with the pink hoses attached. You may know these as the "over flow tubes". 
In reality they are not overflow tubes. While they may allow fuel to escape from them that is not there sole purpose of design. 
They are in fact atmospheric tubes. 
The main purpose of these tubes is to allow the fuel to reach atmospheric pressure. 
This means that when the pressure in the carb body (slide area) drops due to the negative pressure in the engine the atmosphere pushes (@ 14.7 PSI) on the fuel surface helping it go up the jets. 
There are two adjustments on the float level. 
1. The tangs set the fuel level. 
2. The little tab sets the travel of the tangs. 
The "brass tang" level should be set accordingly. 
Remove the float bowl and slide. Place the carb on a flat surface. Get down to eye level with the carb body and you will see two towers sticking up. One tower is the main jet tower the other is the pilot jet tower. Due to casting imperfections I will not supply an actual measurement. 
(This settings is visual and will vary from carb body to carb body that is why I will not supply an actual measurement) 
The brass tangs should project itself to the extreme left hand top corner of the lower tower or pilot jet tower. This sets the float level. 
We will now set the little tab that sticks out perpendicular on the brass tangs. 
The purpose of this tab is to stop the actual travel of the tangs downwards. 
This is important, as it will alleviate many anomalies once set correctly. One must know that the small pointed plunger that the brass tangs pushes up acts like a light switch. The gas is either on or off. With this in mind one need only have this plunger move enough to allow the gas to flow freely and then close when the tangs act upon it pushing up. 
Think of this! When you land off a large rock the weight of the floats push quite rapidly down inside the float bowl. This is known as gravity. The extended movement of the floats downwards tends to do two things. It moves the floats way down inside the float bowl allowing more gas than needed and it also causes some of the excess gas to be pushed up into the jets and into the engine. It also if not set correctly allows the float tangs to travel down to far. 
It is kind of like being inside a fast moving elevator and when it reaches this bottom it kind of makes you bend your knees. In other words the elevator has stopped but you are still going downwards. So how do you set this travel tab? 
Adjusting the travel tab on the carb will not stop the floats from going down but it will stop the float level tangs from traveling all the way down. This is important as the further they travel the more they are likely to stick. 
With carb back on the table and the float tangs set to the previous mentioned setting (top left hand lower tower) you should be able to lift the float tangs about 1/16 NO MORE. 
This bit of play allows the tangs to move away from the plunger jet safely. You will notice that the plunger jet has a springy feel to it. This is allows the float level tangs to still travel up and press continual against the plunger jet for a good seal. The first contact of this plunger will not necessarily close the plunger jet off that is why there is some additional travel afforded. 
The bottom line is that if the gas is coming out of the atmospheric tubes (overflow tubes to you) then the gas level is way to high to begin with. It is not that they are not shutting off it is purely that they are set to high. Keep in mind we are taking about the bike in static upright position with or without the engine running. 
The other thing I would highly suggest is that the pink hose ends be cut on a very sharp angle and small holes placed in the pink tubes. This will help alleviate the siphoning action if it does tend to flow out of the tubes. After all the levels and tangs are set correctly. There is still the possibility that gas will come out of the tubes in some rare circumstances. By cutting the ends of the tubes on a very sharp angle and piercing small holes into the tubes that siphoning action is somewhat cut off. This siphoning action can even after the floats have settled down keep it self self-going. 
Also you should withdraw the pivot pin (the pin the float level pivots on) about 3/8 of an inch and pinch it with some side cutters about 1/8 on an inch from one end and then slide/push it back in. This notched pin will help it stay put in its housing. 
These pins tend to vibrate out and hit against the side of the float bowl (look at the inside of the float bowl for witness marks to this happening). 
One other area of concern on the Beta is the two vent hoses coming out of the engine are far to near the float bowl. In fact mine were pushing against the float bowl this caused excess vibration into the carb body, which in turn plays havoc with the float levels. 
I solved this by cutting the cable tie and having them go around the carb float bowl.

Rob214 Or how about “ I am up under a truck”.

Good name for a Texas rock band “Red Sticky Clay”

You asked me not to mention it again. It was our little secret

If you live in Texas you have never seen mud. Only UK riders know what REAL mud is. Red sticky clay is NOT mud.

A Montesa 4RT battery s not required due to the fact that upon kick starting the circuit sends all current generated by the kick start lever to the EFI starting circuit and only the starting circuit. It is only once it is started do they then send current to the rest of the EFI circuit. A battery on an Ossa is only there to aid in generating enough current at the initial starting pulse.

What where the little white blobs in my carb float bowL? It was very early Sunday morning (6am) heading off to a trial. Only problem was a massive hang over from the night before, and perhaps still a little bit tipsy and in my defense it was dark Needed to mix some oil and gas, grabbed what I thought (of course determined much later after the f*% Up) was a bottle of two stroke oil. I turned out it was a bottle of Armor All. I mixed it with my gas and off out I went. At the event the bike would not start, took the carb off to find little white globules floating in the carb bowl. Yes a drunk Mr Mikuni mixed Armor All with gas and poured it into his new Beta Zero Up side was the rubber intake boot from carb to cylinder head have never cracked

Here goes mine......... I (used to) pride myself on my carb knoweldge. Boy did I get humbled by this one that was self generated by ME. Beta would not run worth crap. Took the carb off only to find lots of little white blobs in the fuel bowl. Any guesses what they turned out to be? Answer to follow

Check this out.

Copemech wrote: "you need to stroke the rod untill you get it all worked out” If anybody knows about stroking his rod until it is all worked out it is Mark

PIP You forgot to add you are a good trials rider. I know I have watched you ride.

Steve You keep hitting you head on the wall expecting a different outcome?

Mark The rotors on a car disc is much thicker than what we have on our bikes. On a trials bike If it does not crack the disc it will eventually warp it if done many times and done really hot. I guess it is all relative to how hot you get the disk. The heat draws out the oil and grease from the pad and disc. Best way I saw a guy clean his brakes was he got them hot and then sprayed the crap out of disc and pad using brake cleaner and then poured corn starch all over them and let them sit for a while. The corn starch drew out oil grease and crap.

I agree whole hardly with 0007 on this matter. I have spoken several times in the past about the in insane practice of pouring cold water on a hot brake rotor. It is a bad and dangerous practice. Here is what I wrote a while back: Some one posted: "I usually perform 2-3 good hard stops from a good high speed run in 5th gear to warm them, then let them cool and resume normal operation. Do this 2-3 times to thermocycle them, then on a final trip do the same to get them and the disk good and hot and douse them with a water bottle to steam off." I wrote: Warning to the wise on getting your disk hot and then dosing it in cold water! I have witnessed this resulting in the disk cracking and or warping due to the aneling effect that the radical drop in temperature causes. I was present when a friend of mine tried this and and then went over the bars after the brake disk shattered after it hit a rock and he broke his collar bone.

Steve??? Mon Dieu..... Oui? mon ami.

Oops. Do Belgium tanks have four reverse gears and one forward gear.

Dabsters boss is Dad of Two, Mother of One.............

Dad of two Well done. Now we all know a little bit about you.

Dad of two Does "Dad of Two” mean Dad of Two Pages for a reply? You said here goes....... I did not learn one thing about you or your skill set training, riding level, education etc All you did was rant about some fraud issues........ Surely you can tell us about you without using you name?

Seems the last few rounds of banter, heated debate, where over technical issues. We have guys on here that speak to their knowledge of torque wrenches, electric pumps, mechanical pumps, and all sorts of others technical prowess. Made me wonder what do we really know about each other? Mmmm Do we know what each other does for a living, what our trades or profession is, what our academic training is? Do we even care? Might be interesting to learn a bit more about each other. I can be found in Linkedin under William Traynor In that vein I will go first: Been riding trials for about 35 years. My riding skills are quickly going to hell in a hand basket (due to two recent big come offs and susbsequent operations to fix torn bicept, torn rotator cuff and broken ribs, and elbow tendonits). Recovery gets harder when you are almost 60. I am not as brave (or stupid) as I once was, I think twice now before going for something big. I would like to think my technical skills are getting better though. Education: Degreed Electro-Mechanical Engineer. Scotland Hold Two Patents: Hold: Six Sigma Black Belt, Toyota Black Belt in Toyota Production System (i.e. Lean Manufacturing, Operational Excellence). I teach T.P.S for a living. I worked for Toyota Europe for 14 years. And you? what do you do? Please post your info............ Linkedin and all...... Thanks

This guy did not get too may views either. Just as entertaining as Bou LOL

I ran across this same thing on a old 315 Montesa a long time ago. A few questions: Is the fuel petcock in the reserve position or normal position? Switch it over whilst the bike is running. What carb is on the bike? Is the float bowl touching the engine cases at any point? What happens if you run the bike on a stand with the gas cap off (with just a little bit of fuel in the tank). What do you observe the fuel doing? Whilst the gas cap is off and the engine is running put the palm of your hand over the gas spigot closing it off, does the bike stop after a minute or so, does the idle change? What happens if you put your thumb over the hose, and or stuff some cotton wool or something else into the end of the fuel hose or even fold back and close off the hose to the atmosphere in the end of the fuel hose, does it eventually stop the engine? Please let us know the answers to these questions. BillyT

I thought there was 25 letters in the alphabet............. I dont know Y.............

How do we explain this then........... 3,146,400 views. Professionally filmed, excellent content, exciting stuff even to non bike riders.