Viking Trike - Need Advice By tomcat (Read 811 times)

[tomcat]

Hit 50mph indicated (which is probably 45 or so actual) the other day for the first time. Was turning 6800 rpm. Trike has 225 miles on it so not totally broken in yet.
Can someone please interpret this info (6800 rpm at top-end speed)?
Is this about right or should I make some adjustments to the weights/variator?
List of mods is in sig.
Thanks!
Tom

[Alleyoop]

First of all why the 30mm carb when a 150 only needs a 24mm carb which is what they come with. The 24mm carbs come with a 35 pilot jet and the main jet anywhere from 103-107.

If you put on a free flow muffler you up the main jet by two from whatever is currently in there if you then add a free flow air filter you up the main jet by two as well. So IF you have both free flow filter and free flow muffler you up the current main jet by 4 sizes. So the most would be around 110 -112 main jet.

Your current setup problem is to much fuel causing less power basically your flooding the motor. The 30mm carb sucks in a HECK of a lot of fuel as well as Air and if the INTAKE you put on to except the bigger carb is bigger than the MOTORS intake that is disturbing the air and fuel flow into the motor.

Most people think let me pour a gallon of fuel into this motor for more power that is not the way it works. A motor can only burn so much fuel and air due to its displacement and fire power as well as being able to get rid of the burnt fuel out the exhaust. If it cannot get rid of it, it acts like a plug it backs up and lowers the motors power. You can see what happens plug up your cars exhaust or even your lawn mowers exhaust you will notice the difference as well as hear the motors rpms drop.
Alleyoop

[stevespidel]

Amen to that Alley. I have the same trike and I've been screwing up performance for 4 months before I got it close to right again. I also have the 30mm carb from Scrappy, but I purchased the kit with the filter and 30mm Al intake manifold. Air cleaner had clearance issues so I tried to run without one while I waited for the new one to arrive. At the same time, I pulled the little restricter doughnut from the end of the mufler and opened the EGR valve on the exhaust header. I couldn't even get it to start without blipping the throttle 3 times and then holding it half open with one hand and choking off the intake with the other. That was fun cause 1/2 open when she fires is launch RPM. Installed the new air cleaner, capped the EGR valve and she runs great now. Can't road test her cause she wants the axle mod. As for the 30mm carb, if Scrappy sold that carb in 24mm I would have jumped on it. The quality and the "pumper" feature are well worth the effort. I have this question, though. Can the stock fuel pump,filter and 3/16 lines provide enough flow for his carb/exhaust setup? I have no fuel pump and run 1/4 lines and a hi flow filter from the tank to my 30mm carb. Heck, half the fun of this is trying to figure out what I screwed up.

[tomcat]

First of all why the 30mm carb when a 150 only needs a 24mm carb

As Steve mentioned, this particular carb is only available in 30mm. I have no idea what the jet sizes are.
It runs strong from launch to 45 indicated, then takes awhile (10 seconds or so) to squeeze out the last 5mph.
I've lowered the air pressure to 15 psi rear and 20 psi front to help from getting bounced off the thing when hitting road bumps. The rear tire sidewalls have absolutely no flex.
What is your top-end Steve and at what rpm?
And what is the problem with your axle?
Tom

[stevespidel]

I had no problem with 55, but I'm doing some custom work and am waiting for a front brake line to be built. 55 is to fast for only the rear brake. I hated the position of the handlebar and the battery pod on the downtube was just ugly to me. I pulled the factory guage cluster because it was big, heavy and didn't provide a lot of info. Replaced it with a Trail Tech unit designed for the Ruckus. Much more useful info and seems to be more accurate.

The axle is something that you should check out ASAP. It's a design issue that was supposed to have been corrected on the new units, but my 2012 shipped with out it. Do a search for axle noise or something like that. There is a thread on Scooter Professor called Wheel Wobble where Alley walked me through the procedure. Alley has been very helpful on that and has developed a simple fix. Basically, the axle can move more than it should and not engage the hubs properly. It will cause serious damage if not caught early.

Have you noticed that there is very little clearance between the tire and fork on the non-rotor side?

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