Just got my friends yt175 tri moto going but it wont idle. Float level 2 low I think?

[mattb348]

I just got my friends tri moto 175k (1983) going! It seemed to run pretty good (and drive pretty good) but it wont idle for the life of it.

I think the float level may be to low. If you hold the throttle just a tiny bit it will run (at idling RPM's) just fine. But as soon as you let off the throttle it does pretty much instantly. I have tried tweaking the air screw but doesn't affect it. Neither does the idle screw.

If the float level was to low it would not idle, since the pilot jet sits higher up in the carb than the main jet, right? So if the float level was lower than the pilot jet and higher than the main jet, it would run, but not idle???

Seems like it will be a good running bike once it will idle

I took it for a spin and it drives good; no tranny or clutch issues woohoo! Good wheelies too.

Also, is it even possible to check the float level using the clear tube method? I could not even find a screw to let the gas come out of the overflow hose

[tri again]

I just got my friends tri moto 175k (1983) going! It seemed to run pretty good (and drive pretty good) but it wont idle for the life of it.

I think the float level may be to low. If you hold the throttle just a tiny bit it will run (at idling RPM's) just fine. But as soon as you let off the throttle it does pretty much instantly. I have tried tweaking the air screw but doesn't affect it. Neither does the idle screw.

If the float level was to low it would not idle, since the pilot jet sits higher up in the carb than the main jet, right? So if the float level was lower than the pilot jet and higher than the main jet, it would run, but not idle???

Seems like it will be a good running bike once it will idle

I took it for a spin and it drives good; no tranny or clutch issues woohoo! Good wheelies too.

Also, is it even possible to check the float level using the clear tube method? I could not even find a screw to let the gas come out of the overflow hose

I'm so smart, I'll run across the field and shut off the bike and turn off the gas like I'm supposed to.

Then I'll get back on it, fire it up and get almost all the way back to the barn and it dies....forgot to turn the gas on,
But it runs perfectly until the moment it dies because the float bowl is empty...so just HOW critical can a float level be?

seems mostly to prevent overflowing is all i can think of,
and I don't know anyone who agrees with me either.

[mattb348]

Float level is more important than you think, not just when it spills out the over flow because it is to high.

The reason your bike runs good until the float bowl runs out (with gas turned off) is becuase you are driving/moving, thus rattling the carb, which is probably splattering every last drop of gas up high enough for the jets to suck it up. And I bet you didn't stop to let it idle half way back through the feild either

I dunno... logically if the float level was to low then I wouldn't think the bike would idle, since the slow jet is literally like an inch higher up in the carb compared to the main jet / needle jet area. At least on my friend's yt175.

Also, if the float level is to low, the bike wont even start at all, because it can't even suck any gas up (I have seen that happen). Another thing that can happen if float level is to low is that the bike can scream for awhile down the ride, wide open, then dies out and you have to wait about 5 seconds for the bowl to (half) fill up again before it will start again (I have seen this happen too).

Of course... the float level wasn't even the damn problem with my friends POS YT175 (No offense to any yt175 owners... I'm just venting because this bike has really started to frustrate me... once it runs right I will love it lol). I have yet to figure out what is. I adjusted the float level, made sure there were no hoses/holes that were NOT plugged off (I removed the stupid oil injection), and i even checked the reeds, which seemed fine.

Now I gotta test the compression, which does actually feel pretty weak when pulling it over. Next step would be check the crank case seals, which I REALLY don't want to do.

Unfortunately for me, my friend can't fix CRAP....... so the only way he is going to have a trike is if I do it all myself pretty much

[Vealmonkey]

But if you try and adjust fuel/air or turn the idle screw and nothing happens, it must be the float right? I think the carb has other issues. Here's something, instead of asking people if adjusting the float makes a difference, since you have the trike at the end of your hands, just adjust the float and see if it makes a difference! Let us know what happens. It seems like it wouldn't take much longer to adjust the float then it would to stop what you are doing and go to a computer, log on, sign on here and start a thread. Let us know please how the float adjusting turns out.

[mattb348]

But if you try and adjust fuel/air or turn the idle screw and nothing happens, it must be the float right? I think the carb has other issues. Here's something, instead of asking people if adjusting the float makes a difference, since you have the trike at the end of your hands, just adjust the float and see if it makes a difference! Let us know what happens. It seems like it wouldn't take much longer to adjust the float then it would to stop what you are doing and go to a computer, log on, sign on here and start a thread. Let us know please how the float adjusting turns out.

I already did adjust the float. Did you read the post above? (the part where I said "Of course... the float level wasn't even the damn problem").

Also, when I made the thread, I was not even at my friend's house, and I wasn't going back there until the next day. So I couldn't just run outside and adjust the float level.

As far as other carb issues.... I went through the WHOLE carb beforehand, cleaned out every air/fuel passage, all the jets, and the whole carb is in great shape, nothing clogged, float valve definitely not sticking, it has all the right jet & needle jet numbers. I also checked the intake boot, reed valvles, and so on. No issues that I could find.

Sorry if I annoyed you. Guess people are getting sick of all my questions already

[Vealmonkey]

Look man, You know how many people say they have cleaned a carb and have done more bad than good? I won't even take a carb apart without replacement gaskets or a carb rebuild kit, it's just not worth the effort. And what people don't seem to realize, if a previoius owner tightened down the aif/fuel screw or the idle screw, then they either more than likely ruined those adjustment screws or ruined the carb. Also if any air leaks around those screws, then the carb won't work right. Also I've never been a big fan of blowing air through carb passages. I've seen more people force crud into a carb and get it stuck then I care to think about. I use a can of carb dip that you can get at your local auto parts store. The only thing I use one the carb passages is cans of carb cleaner. But there are just times, that no matter what you do, that these old carbs have been beaten so much that they are just pieces of junk. My biggest box of junk parts are for honda carbs. I try to save everyone I get and sometimes if you get enough junk carb parts together, you can make a decent carb. But it often takes a ton of cleaning and swapping and bolting and unbolting. I know your frustration. And alot of these cheap new carbs on ebay are no better than what you have which is really a crappy feeling, trust me. But how many times do you think people post on here that there carb isn't working or that they don't have spark? Watch the forums for a few days and a few weeks and find out. At times I would think people shouldn't be allowed to post a question until after they have gotten a shop manual and read through it. It would save alot of space and frustration on everyones part. People seem to forget that these machines are 25 plus years old and that parts are getting harder and harder to find. Some of these trikes people get and are trying to get running look like they've been pulled out of a lake. I wish more people would do a little more research and more searching on here.

[Logan Mathwig]

hey guys im new here! I have a 85 ytz250 anybody got any tips or tricks for me?

[Dirtcrasher]

^ Yes, I have a wonderful tip for you Start your own thread and ask specific questions. Tips or tricks? How to lock it? How to store it? What tires to run? What are the problems associated with that model and so on and so forth............ BTW - Welcome to 3WW

Apparently your float is adjustable, many are fixed. Like VM said, allot of carbs are ruined from people overtightening air or fuel screws. If you have the float set at the right height (and it doesn't leak", it isn't the float. Could be the pilot or air/fuel screw.

Allot of those air/fuel screw tips are ruined as is the hole they bottom on; As well as missing an oring or having a flat one in there or having it in the wrong order.

Keep thinking!

[mattb348]

Thanks for the extra tips. I never thought of the air screw being ruined by being over-tightened. The throttle stop screw is fine; I already checked that and it functions fine. I can make the bike idle, but only if it opens the slide far enough to idle at about 5,000 RPMS

Perhaps the air screw/hole is ruined or something isn't right with it; never thought of that.

See, this is why I like to ask questions. Yes, it may annoy some people (sorry), but look at how I just learned some new things, which I DO appreciate. Thank you guys.

P.S. I didn't clean the carb by blowing air through it, I cleaned it by taking everything out and spraying carb cleaner through everything.

I always make sure the carb cleaner flows good through ALL passages and jets, and I also like to blow through them after too, just to make sure. I never use pressurized air to clean them though.

Guess it is time to take another crack at that old beast. Of course, I still need to check the compression before I bother ripping the carb apart again.

Oya one more thing... if I spray carb cleaner near the air screw while the bike is running, will it make it rev up if there is a bad enough air leak there? Or will it rev up regardless, since it is probably letting air slip through to some extent anyways?

[Vealmonkey]

Are you running an airfilter? Do you have a lid on your airbox, if not, it gives the bike a lean condition, more air than fuel and the trike will rev out, almost a death rev.