This is bullcrap..... hesitation.

[RoyalStarRider]

Me and a couple of buddies went out and rode for several hours yesterday, during the ride we discovered my brake light was stuck on (in a different thread) and while I had the lower fairings off the bike I opened up the holes in the filter covers to let it breathe easier (still has OEM style filters)

 

Today I took the plugs out, cleaned them, checked the gap (.035) and did just general maintance. Then I put everything back on ensureing the plug wires went on correctly.

 

When I started the bike back up it ran very smoothly (my bike has always had a lope to it) and it revs so much more freely... just like I thought it always should. So I take off on a short test ride and the bike pulls out just fine and as long as I ease into the throttle it runs better than ever.

 

Now... when I crank the throttle in say 3rd it sputters, hesitates and eventually clears and takes off like a bat out of hell. If I'm just cruising in 5th and give it the fuel it just sputters and hesitates without taking off.

 

 

I've been building cars and modifying cars for better than 20 years and I know what little I did to it shouldnt have caused this.

 

The only other thing I did was to make sure the clams that hold the plemium to the tops of the carbs were tight... thats it!!!

 

I filled up on my way home but its was at the same place I always get gas in all of my vehicals (shell station) so the possibility of water crossed my mind so I used a little gas dry and some SeaFoam in it and it has gotten just a tad better but it just amazes me how quickly this started.

 

Any ideas???

[M61A1MECH]

My 07 Venture did just about the same thing when I opened up the air boxes. After I reshimmed the diaphram needles by one washer, it was back to normal no more hesitation.

[RoyalStarRider]

I think the next thing I'm gonna try is to fatten up the mixture. The bike has a very free flowing exhaust on it (aftermarket mufflers plus I did a little modding to it as well) if that dont work I'll look into trying the shim thing.

[Squidley]

Before you jump into a lot of tearing apart 1 suggestion would be to make sure you have a good Carbtune sync on the bike. misadjusted carbs can make a lot of things funny, this is where I would start and then go further into it.

[RoyalStarRider]

I just sync'd the carbs less than 10 days ago, so it shouldnt be that, since I havent touched the carbs since I did it.

 

But good call on your part.

[dingy]

Try putting some duct tape over the new holes in the air box. See if that eliminates hesitation.

 

I know the first gen's didn't react well when the air box was opened up.

 

They would start & idle nice, but had similar symptoms as you are having.

 

Gary

[skydoc_17]

On the First Gens. The Plug Wires can be removed and new wires and Plug Caps can be added easily. I have seen recently, on a few of the older Second Gens. that the plug wires are moulded into the coils and I have had a few of these bikes run like crap until I snipped a bit off of the end of the plug wire and added NEW NGK Plug Caps to the old wires.

(I hate to admit this but I got the Idea from V7Goose:doh:, LOL, he was kind enough to share this info in another thread) Well, sure enough, with the addition of new plugs and the new plug caps, these older bikes ran much better. Finally, when ever my bike starts running different, the first thing I do is check the Carb. Sync. Especially if my bike has seen Wide Open Throttle ( Which is...all the time) If I go to the trouble to remove a spark plug from a Second Gen. I ALWAYS put a new plug back in. Even with a Crystal Ball, I havn't been able to figure out the difference between a "good plug" and a "bad plug" just by looking at it.

Earl

[RoyalStarRider]

Its not always possible to put new plugs back in, our somewhat local Yamaha dealer caught fire a few weeks ago and hasnt reopened yet so its a 60 mile (each way) trip to the next closest one.

 

The plugs looked new and the burn on the tips looked great, actually they were almost textbook looking.

 

After sleeping on it I'm feeling pretty confident its just leaned out a little and adjusting the air/fuel should take care of it...... but theres always the chance I could be wrong.

[Monty]

Plugs can be bought at any auto parts store.

[ctraylor]

I drilled holes in my airbox and had to tape them up because of hesitation.

[frankd]

Is there any chance you have water in your gas?? I've had that problem with both of my Ventures. The gas tank vent hose is right in front of the rear tire. When you're riding through a downpour water can be drawn up and into the gas tank. It shows up when you open the throttle. Then the water that accumulates in the carb bowls gets drawn into the main jets and the bike stumbles. To verify if this is the problem you can turn off your gas tank petcock and remove the fuel filter. Then using a clean hose, blow the gasoline out of the fuel filter onto a concrete surface. If you have water it'll collect into the low spot on the filter and when you blow the gas onto the concrete you will see drops of water.

 

Also, if it is water, it will cure itself. Today's gas with alcohol in it will absorb water and it'll pass through with the fuel. However, with 10% alcohol, it can only absorb about 5% water, so it takes several tanks.

 

Frank

[hunter 1500]

This is the very reason I'm leaving mine completely stock. This bike is fast enough without any mods anyway.

[RoyalStarRider]

Its been a long day.........

 

I've tried taping the holes back over....... no help

Fattened up the mixture a full turn.... helped a little but not much

ran some Seafoam through it..... no help

tried gas dry (in case of water in the fuel)......... no help

 

Oh By the way... when running stuff like seafoam or gas dry you need to switch it over to RES, if you dont it'll all settle out in the bottom of the tank and do nothing.

 

 

I cant believe all of this from drilling 2 holes and cleaning the plugs.

 

 

 

One more thing... good luck on getting any plugs for a Yamaha around here by just running down to the local auto parts store.... I can assure you they are an order item.

[LilBeaver]

...

 

Now... when I crank the throttle in say 3rd it sputters, hesitates and eventually clears and takes off like a bat out of hell. If I'm just cruising in 5th and give it the fuel it just sputters and hesitates without taking off.

 

...

 

Okay, so this may be quite basic but about what speed are you at that you are rolling on the throttle in 3rd or 5th? Is it possible that you are just lugging the engine?

 

Seeing as these motors are really designed for peak performance in the upper rev range the behavior that you have described (especially after 'undoing' the holes you punched out and finding the same behavior) sort of seems to me like this may be what is going on.

I do realize that you say you have been working on cars and bikes for a long time, but if you are used to V-twins, that could be part of the problem.

For what it is worth, on an RSV one can do ~94 in 3rd gear - I don't usually shift out of 1st until ~20. I don't usually get out of 4th unless I'm doing 65 or 70. I can duplicate the symptoms that you describe by getting up to about 45 or 50, get into 5th, then roll on the throttle really hard (it will buck and complain and not really start going well until getting up to 75 or 80, and even then I can drop it into 4th and really take off). Similarly with 3rd around 20 except that it will eventually really take off in 3rd.

 

The other possibility that comes to mind is that maybe a bad [or intermittent] coil.

 

Just trying to offer some additional perspective here.

 

 

Oh, for what it is worth, my local autozone carries the NGK DPR8EA-9 plugs. I presume other shops do to, but I've never investigated them because autozone has them at a decent price and they are the only ones that haven't (thus far) given me a good reason to not shop there (compared to NAPA, advanced auto, O'Reilies, etc).

[tsigwing]

This is the very reason I'm leaving mine completely stock. This bike is fast enough without any mods anyway.

[RoyalStarRider]

Even at 60mph in 5th if you roll into the throttle it starts sputtering and missing.... I still find it hard to believe this all started from cleaning the plugs........................

 

Earlier today it would do it in neutral but after fattening up the A/F mixture it started reving right, but with a load on it still does the sputtering.

[1BigDog]

One more thing... good luck on getting any plugs for a Yamaha around here by just running down to the local auto parts store.... I can assure you they are an order item.

 

I get my plugs from O'riellys auto parts. Always in stock.

 

Now as far as the hesitation goes, my 99 was doing that a few years ago. Another member, Muffinman, used a tool called Colortune to adjust my carbs and havent had any more hesitation since. Before the Colortune I always had to drop a gear going up some bridges in town if I was in 5th. Now it just pulls steady up the bridge. With a Colortune you actually adjust the fuel/air mixture based on the color of the flame in your combustion chamber.

Its also possible that your fuel filter may need to be changed too.

[RoyalStarRider]

Wow... you guys were right, they actually had the plus at AutoZone....... this is the first time I've ever been able to get a NON auto plug without haveing to special order it.

 

I guess I'll be putting new plugs in tonight..... and draining the bowls (just in case)

[RoyalStarRider]

Well it was a long day but I made some awsome progress.

 

I started out by installing new plugs, pulled the carbs off and drained the bowls (didnt realize I could do it with them on the bike) and I also drained the tank...... i think I got some bad gas on top of everything else...... I also readjusted the A/F mixture. apparently stock is 2 full turns out and I have mine set at 2 1/2 turns.

 

All of that really helped the issue but didnt cure it...... luckily I tried one last thing.

 

I sealed the holes I cut into the filter boxes and re routed the hoses that went to them. I didnt realize the hoses were the vents to the diaphrams on the carbs, so after getting them back into original configureation I started it up and went for a test ride.

 

This is the best its ran since I bought it, I can definitly say that the carbs need to be fattened up from stock.

 

Thanks for all your input!!!!

[tnt05venture]

You will have to shim the needles if you want it to quit hesitating. The extra airflow means its not getting the fuel quick enough. Had mine tuned up and I read about the air box mod and tried it. When I was running at low rpm's and rolled on the throttle it would bogg down for a couple of seconds but, if I had my rpm's up and rolled on the throttle it get on with it. I never ride in 5th at 60mph maybe 75 because it luggs the motor and it makes mine drink the gas. IF I ride at higher rpm I get alot better milage JMHO:cool10: