|
|
Post by geh3333 on Dec 28, 2015 22:50:03 GMT -5
There is a lot more to power brakes then there is in one of the vacuum valves. correct. the vacuum booster on power brakes is just one item that make up the brake system, just like the vacuum valve is one item in the fuel system. the vacuum booster is essentially a big vacuum valve. they don't go bad as often as they are being used outside their design specs. the majority of 50cc owners seldom have problems with them. noted for future reference. so, just when are we to take you seriously? To be honest , most that ive seen go bad where on 150cc scoots . not sure if there may be a reason for that . If it seems kind of out there , then its prob sarcasm , lol |
|
|
|
Post by JR on Dec 29, 2015 0:16:42 GMT -5
Experiences vary, myself I have a 2009 50c scooter that has the OEM everything on it. I don't ride it much, in fact it sits more than it is ridden but I started it today and let it run for about 30 minutes, weather was horrible so riding it was out. It has a vacuum petcock and all the original vacuum lines still in place, only better quality ones put on when I did the PDI on it.
Have two 250 scooters both with the linhai clones, one a 07 the other a 08 both are still running and only thing replaced on them was the OEM vacuum fuel pumps and that was only because I found a great bargain on some Mikuni vacuum fuel pumps and I knew they were better quality.
The one draw back on a electric fuel pump to me is the threat if one is out on the road and has a electrical charging issue you'll not have any fuel delivery. Not the case with a vacuum pump system.
JR
|
|
|
|
Post by geh3333 on Dec 29, 2015 0:31:46 GMT -5
I would keep a spare mikuni under the seat .
|
|
|
|
Post by geh3333 on Dec 29, 2015 0:36:35 GMT -5
The fuel pumps and fuel valves are a different animal. In many cases a fuel pump is necessary but with a gravity fed system the fuel valve is just another problem waiting to happen . yes. Many have no issues , but at the same time many do . its just nice not having to deall with any vacuum issues.
|
|
|
|
Post by rockynv on Dec 29, 2015 2:43:07 GMT -5
Remember that foam air filters are only semi-permanent and still require replacement after one or two cleanings as the foam starts to break down which happens more rapidly since ethanol came into use. A one cylinder engine develops a pulse that flows back through the intake which is what allows the vacuum fuel pump to operate and mists a little fuel vapor back at the filter which when laden with ethanol rots away at it until it eventually can tear and be sucked into the cylinder along with all the dirt it contains. Myself in the past 50,000 miles of riding scooters instead of motorcycles I have not had a vacuum shut off fail of its own but have had bad vacuum lines and intake parts fail preventing enough vacuum to open them (so far not on the Aprilia though). I've had the same foam uni filter for 20,000 + miles and its still going strong . it wouldnt be worth the $30 for a foam unifilter if you had to replace it after a couple cleanings. Not everyone has the more expensive foam UNI filter and the more common OEM type foam filters do fail quite often. I usually replace the OEM foam filters with an ethanol resistant version from Mallossi or another vendor of Ethanol Resistant Foam Filters. After counting the costs of purchasing and maintaining a UNI filter along with what you give up removing a port tuned airbox in a well designed intake I am not a big fan of the pricey filters anyways. Remember I ride a fuel injected Aprilia which has a tuned port intake for better low/mid-range torque and it works quite well as it comes from the factory. Note that the tuned port length and diameter can be critical on a carbureted bike since that helps maintain the intake pulse and vacuum required to operate fuel valves and vacuum fuel pumps. All part of the equilibrium of the intake. |
|
|
|
Post by geh3333 on Dec 29, 2015 8:36:21 GMT -5
You do have a point with the cheaper foam filters . I'm not sure myself , how long they last compared to the way uni filter , but I'm sure its not nearly as long .
|
|
|
|
Post by JR on Dec 29, 2015 12:08:54 GMT -5
I would keep a spare mikuni under the seat . When I bought the Mikuinis it was a dealer going out of business on Ebay, just a luck find, normally they are $30 to $40 each, got 3 for $5 each and along with them 3 rebuild kits at $2 each again just pure luck. Mikuni's can be rebuilt but the ones on my scooters are now 6 years old and still pumping, the 3rd pump in my desk drawer along with the rebuild kits. All pumps can go out including electrical ones so that's a wash there. Like in all things it's what one prefers and wants. If I had a scooter that I fully believed was having fuel delivery issues or even one that I have pepped up then for sure I would want to upgrade the fuel delivery, if gravity fed I probably would go to a manual valve and before I did I would pull the carb, make sure the float was adjusted well to allow maximum fuel and yet shut off well in case I forgot to shut the manual valve off. I've got a Husqvarnia mower that makes me angry because it has problems with the carb not shutting off when the engine is off. You go back a week later to mow and the whole engine is full of gas from the tank. The tank is huge and holds nearly 3 gallons of fuel which means heavy. The float will not hold the pressure. Took it back for warranty repair 3 times, ended up putting a manual valve on it myself. Some people like the electric fuel pumps and have great success with them and with the newer scooters having better electrical systems they will support the voltage needed for one. Some of the older 6-coil stator scooters struggle or won't even support electric fuel pumps because their systems are so borderline they barely support the existing electrical on them. Like with all things pros and cons. JR |
|
