I think someone asked why go over the intake manifold with the fuel line, and my reason is very simple... Appearances. I didn't want it showing. I wanted as much engine showing, and as little of anything else, as possible.

Being up here in the NE, we don't get to run 90, hardly ever... unless we have a death wish, or would like to make appearance in court.

I can't say anything other than I rarely get to run even more than 60... but, then, most of my riding is on back roads where I am so very often running 35 to 45. I call it toodling, and I very much enjoy to go lazy riding on back roads in 4th gear... the older, the better. I can get on our interstates and run our speed limits, but the highest we've got is 65.

I look for, and ride as much of old colonial era New England as I can find. Much of what we have locally goes right back well into the 1600's. We're coming up on 400 years in this locale, and my own forebears came here in 1635!

So, I could perfectly understand if I might need other mods, were I to ride with any of you others in the manner you do.

I can see now why you've not had a problem using the stock float valve. My experience with it was that the float bowl would empty at about 75 full throttle. I probably could have changed that by raising the float level some but I never tried.

If I could somehow convert the bowl vent to internal I could probably raise the top speed with the Grizzly. If anyone has any ideas about how to do that I'm listening.

I have an 05 RS 1700 that uses the fuel pump and its never had a problem so I'm wondering why others owners feel the need to remove it? I assumed the reason for the fuel pump was to prevent vapor lock in the big air cooled V-twin. I don't think Yamaha just installed the pump for looks but IDK. Are these pumps failing often or is there some other reason to remove it.

They don't fail often but they can cause an overflow condition in the float bowl when hot...I took mine off for looks mostly..

Dick M. wrote:
I have an 05 RS 1700 that uses the fuel pump and its never had a problem so I'm wondering why others owners feel the need to remove it? I assumed the reason for the fuel pump was to prevent vapor lock in the big air cooled V-twin. I don't think Yamaha just installed the pump for looks but IDK. Are these pumps failing often or is there some other reason to remove it.


The fuel pump is all about regs and the desire for a supposedly safer motor cycle......"my bike fell down, but look!!!!! It didn't leak any fuel. Now I have the warm fuzzies"...............and, the 40mm Mikuni, is what Yamaha chose to put on the Roadies(think regs and economics), and it is a a pump specific carb.
I've dumped the pump on both of mine, as have countless others, mostly because it is just one more thing to cause problems(when it does). Gravity never sleeps. When you're sitting on the side of the road in the middle of nowhere, because the pump took a crap, all the feelings in the world won't make a difference.

As a plus, getting rid of the extra crap allows the motor to get more air. It is an aircooled motor after all. Why trap the heat under the tank?
Anybody running an HSR 42 instead of the stock 40, has ditch the pump. The HSR's, are a a pumpless carb. They have a larger needle and seat, and a bigger bowl. Many members have ran the stock carb doing nothing else other then removing the pump. Done properly...IMHO, the grizzly valve should be installed. It is a true gravity flow needle and seat, and is twice the size of the stock pump style needle and seat.

I'll also say, where you will starve the bowl with just the stock needle and seat is at those times when you are running WOT for prolonged periods of time. Think rpms over 3000, where the carb is sucking all the fuel it can get. As the rpm's come back below 3000, the stock needle and seat, is capable of replenishing the bowl.

With the 40mm carb and the grizzly valve, I have run over 3k for many miles, without a hiccup. I could starve the bowl using the Suzuki 2.3 needle and seat, but only after WOT through 1st and 2nd. Right when I'd hit the limiter in 2nd, and be ready to shift to 3rd, it'd stumble. That was riding two up.

Cut corners. Lower the rear of the bike, and you'll have some issues. Mainly because the petcock is in the front of the tank, and not the rear. as the fuel moves to the back, it uncovers the petcock tubes. Run the petcock on reserve, and you will avoid most of the issues. If you run out of fuel because of the pumpless mod, it is because A., you probably lowered the bike. B., you waited to long to fuel up. C., you didn't know the bike had a reserve.

I run my fuel lines under the manifold. Its all about form and function. I'm pleased enough with the function, I'll let form ride on the pillion.

I'll also say.....because I have so many friends ......if you had problems going pumpless, its operator error. Get a different mechanic. Rule number one. Get advice from those who can do it. Not from those who say they don't think its possible.

....just a sec. I need to refill my margarita glass.

Dick M. wrote:
I have an 05 RS 1700 that uses the fuel pump and its never had a problem so I'm wondering why others owners feel the need to remove it? I assumed the reason for the fuel pump was to prevent vapor lock in the big air cooled V-twin. I don't think Yamaha just installed the pump for looks but IDK. Are these pumps failing often or is there some other reason to remove it.

I'm 1 of the few here that agree with you. I even installed a smaller float valve on my HSR45 carb so I can use a pump. There is "NOT" a high failure rate of the fuel pump. Some take them off because a perfectly good pump "May" go bad someday. Others say they take them off to get rid of carb puke or the possibility of carb puke instead of solving it with the pump. Some say it allows more air to the rear cylinder even though it don't need more air to the rear cylinder, and then you got those that remove it because they just want to do a mod and going pumpless is a mod that can be done on the cheap.

The term "reach around your arse to scratch your elbow" comes to mind. That is, the very definition of a fuel pump, on a motorcycle. At least, on a Road Star. Granted some styles require an extra elbow to get fuel to the carb.......but then, that's why......fuel injection.

I carry a brand new spare pump in the trunk, will I need it?....maybe.....if I do, I'll have it!.....not to hard to change out. Plus I all so have 3 ft of fuel line in there as well.....Just incase.


Perry

Carry a clean pair of drawers, also. Just in case. Just in case.

davej wrote:
Dick M. wrote:
I have an 05 RS 1700 that uses the fuel pump and its never had a problem so I'm wondering why others owners feel the need to remove it? I assumed the reason for the fuel pump was to prevent vapor lock in the big air cooled V-twin. I don't think Yamaha just installed the pump for looks but IDK. Are these pumps failing often or is there some other reason to remove it.

I'm 1 of the few here that agree with you. I even installed a smaller float valve on my HSR45 carb so I can use a pump. There is "NOT" a high failure rate of the fuel pump. Some take them off because a perfectly good pump "May" go bad someday. Others say they take them off to get rid of carb puke or the possibility of carb puke instead of solving it with the pump. Some say it allows more air to the rear cylinder even though it don't need more air to the rear cylinder, and then you got those that remove it because they just want to do a mod and going pumpless is a mod that can be done on the cheap.

I'm with you on this dave, if it ain't broke there is no need to fix it.