Topic: 750 K carbs

[oldman prof]

Hi there,my carb floats are not round like all the pics , they are the odd shaped black ones.What I'd like to know is were to measure the float hight(high center low) having a flat bottom(top if you holding it upside down).I have all the charts but I'm not getting it right.Can it be I'm measuring the wrong place?
I think it's a 78,there are 2 screws holding caps into place on each carb
Thanx  You guys are doing a great job

[SohcCBs]

I'm not sure which carbs you've got, but I think all are measured from the bottom of the float (right side up) to the bowl gasket surface.  Do the float valve pins have a spring loaded nipple making contact with the tang of the float.

http://www.salocal.com/sohc/tech/carb/asmpg_mgs/flthgt.htm

Even if you've got different bowl, this may give you the idea.  Which manual do you have?

[oldman prof]

Ok,if I hold the carbs upright as they are on the bike,the floats will be hanging down so if you measure at the needle&seat end, the distance from float bottom to carb body is less than the part of the float thats furthest away from the needle &seat.I know it sounds complicated, I'll try and post a pic tomorrow, it does'nt have a round float so I can't find a high point(or low point if its hanging)to measure.
I know it can't be but I hope it is'nt a one off.All my manuals are from 69-74 and as far as I know this bike is a 78
Yes they are spring loaded, everything's the same(in the float bowls)exept for the shape of the float

[SohcCBs]

Ok, I was using the upright position just so you'd know what exactly to measure, but if the float valve pin is spring loaded, that must be taken into account.  At the url above you'll see the measurement must be taken while the carb is held at an angle so that the float tang is touching the valve pin, but not compressing it (as shown in the 2nd and 3rd photos).  I am not as familier with the later carbs, but the spring on the valve pin must not be compressed when taking the measurement.   There are people on this forum that are very familier with the later carbs, maybe they'll pickup on this thread.

....any float on any carb, whether round or flat will be meaused from the bottom of the float to the bowl gasket surface, or the lip that goes around it.

[oldman prof]

sohcCBs,I'v got that.What I'm asking is: looking from the side the surface of the bottom of the float and the surface of the gaskit or bowl where you measure from are not parralell(sorry)so if you measure from the bottom of the float to carb body at the float pin end the measurement will be smaller than to far end.Like a sailing boat mast, the deck being the float pin side, where the mast moves a tiny bit compared to the other end. Now where along that mast(float bottom)do you measure how far its leaning over. I'm trying to post some pics of what my carbs look like, maybe I'm just explaining it ass about face,but I will take som pics of my float levels this Sat and put them on
Thanx for the help,Sorry I'm being such a #$%*  http://new.photos.yahoo.com/anthonyhestermann#page1
If you go here to the album marked 750 K carbs you'l see the shape of th floats, I'll take some better pics the weekend

[SohcCBs]

No #$%*s here, just questions that need clarifying......sorry I'm kidding around, but don't worry about it.  I think I understand what you're saying, that when the bowl is hanging it's not paralell so where to measure from.....I would think its lowest point, but I'll try and do some research and get you a better answer.  Like I said, I'm not as familier with the later carbs, but I didn't see anybody picking up on your thread.......so I thought I should try and help.

[oldman prof]

Thanx I'll take any help I can get. I'v try'd to use paint shop on one pic and I'v made a(very) rough scetch, you might have to try and magnify,the carb body is upside down and from the side, the arrow pointing to the one float on the table is the direction I'm looking from.I think I'm getting you more confused, dont worry I'll post pics on monday,I can only strip the carbs on a weekend,it's my transport so the carbs are'nt to bad I just want to make sure that it is correct.I think nobody's picking up the thread because I'm confusing them.

[SohcCBs]

In the supplement section of my Honda manual it states the float height on the '77 is 12.5mm....in the supplement to '78 carbs, it states the float height is 14.5mm.  If you do some preliminary measuring you might find the right location and what year the carbs are from, assuming they're close to right. 

....but I have to ask, if you're using the bike now, why exactly are you trying to adjust the carb floats?  What symtem are you having that out of whack?

[oldman prof]

I think the fuel level is to low in the carbs, after a good hard run it sounds a bit lean,but the main thing is that I know it is not correct and I hesitate to ride it to its potential.

[SohcCBs]

Find a place you can shut the engine off at speed after such a run.....pull the plugs.....or at least don't let it idle much, shut it down and check all the plugs.  Try not burning yourself, but see if the plugs are lean.  If it's making a noticible difference, you might see orangish or brownish plugs.

Any yellowish tint on the headers, up by the head?  I can't say it's tried and true (always), but blue at the top of the header CAN be rich, and yellow at the top CAN be lean.  I've seen that indication on a few of my bikes.

[oldman prof]

Thanx I'll try that on the way home this evening.I leaving work early, see you on the morrow

[oldman prof]

Yes, she is running lean,anything over 5secounds(aprox) at about 7 or 8 thou.rpm and killing the motor the plugs are a too light tan,if I let her idle after that she will pop untill the float bowls fill up.I'll set them to 14.5 the weekend and have a looksee, thanx.

[SohcCBs]

Sounds like you're getting a handle on it..let me know how it goes.

Ed

[oldman prof]

thanx will do

[SohcCBs]

after that she will pop untill the float bowls fill up.

Check your fuel and carb vents!!!  Now mine's a '76 but it's got fuel vents on the carbs and another one inside the tunnel of the gas tank.  Up in the top of the tunnel....you nearly have to turn it over (or up) to see it.

[oldman prof]

That I will look at,I remember having that problem with an older model of mine, that was more than 20yrs ago I must do some more swotting. thanx