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Discussion Starter #1 (Edited)
Hey fellow riders! Well, I am a new guy here on the forum, but I thought I would take a shot at asking my question, with the hopes of getting my issue resolved. I will try to get ALL the details in, so this might be a LONG post. Sorry in advance, but I am trying to be thorough!

Here goes:

Basic stuff:
-2001 Yamaha V-star 650 Classic
- The bike is stored OUTDOORS under a heavy duty cover, between my cars.
-Miles; 3,600KM (Canadian model)
-Owners; I am the third owner. First owner modded it a bit for his wife, second owner never rode it for 2 years, and I bought it from him.
-Owners manual has been read, yes. Sadly, they don’t have any tuning info in there!
-The following mods are on the bike: Aftermarket slip on exhaust (cobra-style slash cut). Changes I have made; 92.5 main jets (90 is factory), 22.5 pilot jet (factory 20’s), 0.020” shim X 1 per needle.
-Searching topic: I have scoured this forum, and tons of other forums – close to my problem, but never a solution that works for my situation

Now for the nitty gritty, and the past history/problems I have had, what has been resolved, and what persists.

I will do it in point form, for easier following:

- Purchased bike from a local guy, when i went to look at the bike, it would fire up right away on Choke (high RPM as it should have), then warm up, and idle nice and steady with the choke pushed in. THE ONLY issue it had, was the rear cylinder would flood a bit and spit fuel. it burned, but poorly, and spit quite a bit of gas (yet it did burn some off). The owner told me that he was trying to clean the carb and broke the little wire arm on the Needle Valve, so he made one out of guitar string. (This was later revealed to be true, and I will get into it in the next point). The bike came equipped with aftermarket slip on slash cut pipes. They are Loud as hell, and they DO have baffles. They technically should not require a rejetting, but I did a minimal uppage in the jets (more later).

-Brought bike home via friend's truck. Step one: Let's get that carb out, cleaned and repaired. Went to bike shop, got a "replacement" needle valve. Turned out to be too short, kept flooding the rear cylinder even worse (thank you tech guy at the shop *rolls eyes*). I ordered a factory needle valve assembly (Yamaha genuine part # 8, with o-ring, mesh screen, etc). Installed it. All jets were cleaned, etc. OK bike was cleaned out, 100% stock and factory spec now. I went to crank it... Nada. Sputter sputter, die. Occasional startup, die. NOTE: here is something weird: The bike has a better chance of being started leaning to the RIGHT (brake lever side).

-OK This is ridiculous, let's work on it more. I replaced the main jets with 92.5 (factory is 90) to help a little with the slightly increased flow from the slip ons. I also used a little seafoam in the gas, to try and help de-gum anything that might have got sticky. *At this point the inside of the carb is 100% fine, no issues from the stock parts*

I was able to get it started by leaning to the right, and took it for a short ride down my street... Coughing, and sneezing back through the carb - all symptoms of being lean.

- I noticed one day, when working on it, that if I take off the airbox, and stick a cloth in the air intake, covering 2/3rds of the air flow, it would start up and run fine, enough that I could ride it.

hmmm got me thinking: It must be running too lean!

- Next changes were 22.5 pilot jets (20 is stock, so not a huge jump, if any jump at all), and the PMS screw caps drilled out, and turned out to 2.75 (2.5 is stock) from seated position.

Went to start it. Hmmm interesting: It will, upon the first crank with the choke pulled out, start RIGHT AWAY, keep HIGH RPM and die after 5 seconds or less. Then it will not respond to cranking, BUT WILL grab and start sometimes with the choke PUSHED IN.

In fact, with the last mods, after only 6 or 7 tries, I was able to get the bike to start, but only with the choke pushed in (aka ZERO choke).

At this point I was able to take the bike for a ride down my street, shift gears, and ride it normally. Only thing I noticed was a bit of sluggishness at 0-25% throttle, aka during pilot jet duties/etc.

SO THE MAIN PROBLEM AS IT STANDS: It won't start easily, choke does nothing really (I know the choke works, as mentioned, on the first crank most days it has been sitting, it will catch and keep high revs for a few seconds, then dies), and is still kind of sluggish at low RPM/0-25% throttle.

Still, no more coughing/sneezing at this point, but starting it is torture.

Any ideas guys?

PS I am aware someone will say I jumped too far with the jets and whatnot, but I feel the changes in the jets are SOOO minute, that it should not affect the bike too badly.

In fact, the new pilot jets seem to have helped the bike a bit!

My thoughts on what I think it could be: Pilot jet pathways are clogged? (I am sure I cleaned them!) or maybe fuel isn't getting to the carb somehow.

NOTE ON SPARK PLUGS: I put in a new set of plugs yesterday, haven't had a chance to try starting yet (Canada = COLD in November).

RANDOM THOUGHT: Is there any chance that, because it is stored outdoors and it is cold lately, that my carb is simply too cold to start? As in, my settings are just fine, but because the temperature hovers around 40-45F, that my carb is cold? (I hard the v-star 650 has carb heater coils, no?)

ANY HELP WILL BE APPRECIATED!

UPDATE UPDATE UPDATE: I made you guys a video to show you how I can get it running by shoving a cloth into the air intake. Clearly an issue with being too lean at start up!

 

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Have you checked properly for leaks in the inlet manifolds. If it runs when you choke the air intake, maybe air is leaking into a manifold?
 

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Discussion Starter #4 (Edited)
To reply to the last two:

Cruza: I thought the same, but I have taken the air intake apart numerous times, and even fixed any places that may have leaks, made sure all clamps are down tight, inspected for cracks and breaks etc. I suspected the same thing as you, but I cannot seem to find a place where it would leak in.

nick57: Well that's what boggles me too. The airbox IS stock/factory. So why is it leaning out NOW all of a sudden? It must be my fault somehow, as the bike started up no problem on factory settings at the guy's place, before I bought it - it merely ran too rich/flooded on one cylinder, but that was resolved with a Float needle valve assembly (new one, with all new pieces).

The ONLY piece that was replaced at the start of these problems, was the float needle valve/and it's housing. At that point it ran like a sick turtle, whenever it did start. Now with the larger jets/shimmed needles, at the least it runs properly when accelerating. (I DID NOTICE when I bought it/picked it up and rode it over to the truck to haul home, that it also coughed and wheezed. So it was lean then too, but at least it started).

Spark plugs (I put new ones in a few days ago, but the old ones are beside me here on my desk) are .... well I can't tell, because of all the tinkering as of late. The rear cylinder one is dark, with the tip being a lighter beige. The front spark plug is dark, which would make me think too rich... but when it was leaned out a bit, it ran like crap, so I don't want to go back to that :(

I am stumped guys!
 

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Discussion Starter #5
Yes the 2001 XVS650 has carburetor heaters. Some (just on this forum alone) state they are needed and some say they are not needed. You might belong to the former. Good luck!

ps.
I understand you are a lumberjack and you're okay
:D
Apparently that's the rumour going around ;)

As for the heaters... I am going to test that theory, by applying a low-setting on my heat gun and gently warming the carbs up then trying to start it. If that at all helps, I will know two things; 1) it is temperature related and 2) its time to move to Florida and hang out with my uncle!
 

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Have you checked the float heights in your carbs? This sounds similar to a problem I had with my Suzuki bobber. It may not be that but it is worth eliminating the possibility.
 

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Discussion Starter #8 (Edited)
Have you checked the float heights in your carbs? This sounds similar to a problem I had with my Suzuki bobber. It may not be that but it is worth eliminating the possibility.
You know, I was thinking that, but admittedly.... I have no idea how to measure/check that :confused:

Could you help me out? Its definitely something I want to look into, as it may be a HUGE possibility (the floats were removed at one point to install those needle valves, so it is the ONLY thing that was really touched after the cleaning, and it seems plausible the problem lays there)

EDIT: Would this be accurate? --> http://650ccnd.com/floatbowl.htm
 

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Discussion Starter #10
in your first post you had a bad float valve so you changed the jetting why don't you try putting the jetting ack to stock.slippons do not require a jet change only a pms adjustment.
Oh, maybe I wrote that wrong? After replacing the float valve/assembly, I tried starting it on fully stock jets etc. No reaction.

It runs pretty swell now, once you get it running (like I did with the cloth). I had it running today, took it down some back roads, and with the cloth covering half the intake, it was pulling hard and strong.
 

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Careful the cloth doesn't get sucked through the carb and into the inlet, can do some damage. Float levels are critical.....it's worth finding the procedure and setting yours. The fact that it can run when leaning over.....sounds as if level may be an issue! How about your air/fuel mixture?
 

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Discussion Starter #12
Careful the cloth doesn't get sucked through the carb and into the inlet, can do some damage. Float levels are critical.....it's worth finding the procedure and setting yours. The fact that it can run when leaning over.....sounds as if level may be an issue! How about your air/fuel mixture?
Yup, I am very careful that it is in there firmly, and only at the mouth of the opening :)

And yes, floats are the next thing I am looking at. I need to find the procedure though, I think the one I posted (this: http://650ccnd.com/floatbowl.htm ) might be it.
 

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That's the right procedure, what you need from a manual or the internet is the exact measurement for your model's float height. Although a bike will run with the height wrong it will only run properly when the float height is spot on.

You really need to know at what height the fuel in the tube should come up to when measured against the side of the float bowl.

On some carbs you can measure the float height by taking off the float bowl, turning the carb upside down and measuring from the flange to the top of the float but I don't think you can do this with the Yamaha.
 

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Discussion Starter #14
Alright, I measured the fuel in the bowls with the help of an "assistant" (my father... oh man, is that man ever fun to work with..).

I made the mark (using the bottom of the curve on the fuel level in the tube) - 4.5 to 5mm below the fuel line mark on the bowl cover.

Technically it is supposed to be 7.5-8.5mm

But that makes no sense, my bike is too lean on start up, so it would need the extra fuel...

I am starting to suspect my CHOKE. The actual choke assembly on the carb. The cable may be moving, and the little arm moves, but the internal mechanisms may not be working as they should be.
 

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You should check your chokes for sure but I would correct that float height too. I know you say your problem is running too lean but running too rich can also give you starting issues.

Maybe by leaning the bike to the right you are allowing the float height to drop and be nearer what you need. Just a thought.
 

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Discussion Starter #16
You should check your chokes for sure but I would correct that float height too. I know you say your problem is running too lean but running too rich can also give you starting issues.

Maybe by leaning the bike to the right you are allowing the float height to drop and be nearer what you need. Just a thought.
Re: leaning the bike - that was my dad's thought. he said that it was probably a sign of float level/gasoline in the bowls.

So Today I am going to check out the choke assembly, and then probably tweak those floats a little bit if that doesn't do it.

One thing at a time, right guys?
 

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Discussion Starter #18
Any progress/news? Don't leave us hangin man :D
Sigh, well good news is it runs once it is (with great stubbornness and difficulty) started up. With a lot of voodoo magic and weird angles, I can get it putt putting, and then warmed up. Once it IS warmed up, it will run no problem with the factory airbox on, etc

Bad news is that I still can't get it to start up cold/easily. I took out the carb Friday, and have worked on it over the weekend (cleaning accelerator pump, choke/enrichment passageways). Also, using a multimeter, noticed the TPS was a little out of whack (Should read 650-750Ohms resistance, but was at 851, so I brought it down to 709-722ohms)...

but then, like an HUGE IDIOT, I didn't just enjoy riding it yesterday, the last possible day to ride in our wonderful city/area (sunny, over 52F, no wind during the day), but rather toyed with that stupid carb.

Knowing my luck, I accomplished nothing, it still won't start, and now it is raining today (another 50F+ day), and tomorrow, and then Tuesday it will be sunny and like 32F. (I am using Fahrenheit for our American friends, since it's predominantly US guys on here :) )

SO the basic update is: I should have ridden it, since it does run, rather than trying to perfect it for the startup issues.

Conclusion: AS OF 10:00Am today, still not running, BUT I AM YET to re-install the carb after cleaning and adjust.

Hoping that the choke work I did, the TPS adjust, and the double checking of pilot/accelerator pump/PMS/etc passageways has done the trick.

Even if I did fix it, I can't ride it anymore. I am LEGIT considering moving in with my uncle down in Florida. I am sick of cold weather. :D
 

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Discussion Starter #19
Spring is here in Canada (almost).... The bike comes out of storage in the next couple of weeks, and I think either the battle begins again (with the carb), or the smarter move: I will see if any of the mechanics around are free and reasonably priced, and have someone else deal with it this year...

So that's my update for now!
 
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