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I wish i could fix stuff by just throwing parts at it.... You must have really good aim or magical powers. I usually have to use tools to atleast get the old parts off.
Who knows maybe when I'm as elderly as you I'll be able to throw parts at stuff to fix it.
Man that will be cool, until then I have to stick to my internets and tools. :/
Maybe you should consider some diagnosis rather than relying on the internet. Also, when you get as elderly as I am you will have some skills and experience to go with your enthusiasm. I feel a little sad to have to explain that the phrase "throw some parts at it" means that you don't have the skills or understanding to figure out what part of a system is causing the problem, so you just start replacing parts until it works. Kind of like when you think it might be missing on one cylinder so you are considering replacing spark units and the ignitor box because you don't know what is wrong. Have you even determined yet which cylinder is not running? Have you determined whether it is spark or carburation? You have exhibited no diagnostic skills yet to the point that you don't even know which are the proper questions to ask.

So, before you make any more weak assed attempts at sarcasm and condescension, gain some more experience, humility and sense. As an engineering student, you suck at problem solving and manners. I have been doing this for a long time and I have seen your kind come and go. So, Sonny suck it up and do some work to figure out what the problem is with your bike.
 
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what an obnoxious fuck you are ,nice peaceful area and you ,who can't even ride safely at 2 mph, out on the street raising a huge fucking racket for why ? so you can be sure it will never run worth a fuck..that is all, those pipes, mindlessly cut up as you have done, will accomplish
but behind that is a selfish need for attention no matter what it takes
if was your neighbor i would putting sand in your engine sump after bitch slapping your mug in rapid fire fashion,.and or do something that hurts you
in the meantime i have an exercise for dumb cocksuckers like you
get an old red brick ,every morning stand on your front lawn ,and continually beat yourself in the face with red brick until the stupid goes away
 

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Discussion Starter #284 (Edited)
Hey guys update!

I put about 100 miles on the bike this summer. I'm still not done but definitely rideable. Here is, aside from a few changes, where I left off in the fall 2017. (More updates as weather in MA clears up, and work on the bike continues.) As always feedback is welcome :)

Thanks for the support and help guys.
20170716094414_IMG_4083.JPG

BONUS VIDEO :p
 

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Two obvious issues with that bike:
It is obnoxiously loud and of course it doesn't run right with those open pipes and pods. It sounds totally obnoxious.

A second issue is the ergonomics with forward pegs and low bars. It is both unnatural and dangerous to ride like that.

Poor sod riding it looks scared witless, which is probably a good thing because it is a bike to be wary of.

You might like to consider leaving it out in the street with keys in the ignition in a bad part of town and hope that someone lifts it so you have an excuse to get a decent bike. :eek:
 

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Sounds like it is only running on one cylinder at low RPM. That bike is fairly horrible, but perhaps it will get better as he learns that it sucks as it is.
 

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Discussion Starter #291
Andddd I'm back.
So put a few miles on it last year, I got a car so i haven't used the bike much this year. But I want to get some riding in this fall. However having some fuel issues.

Recap from last year:
My fuel pump was over heating and shutting off and I could not figure out why!
I bought another fuel cut off switch relay, and a new pump. Tried old pump new relay, new pump old relay, new pump new relay. Nothing worked.
So I just ditched the pump and relay, and went gravity fed. Which worked fine. However being the genius that I am I removed the petcock and flooded my rear cylinder. Hooray.
I drained it, changed the oil and reinstalled the petcock. And thats how I ended summer 2017.

Where we are now:
end of summer 2018.
I cleaned the carbs, I have the floats set high high, so that the bowls can fill more. Fuel is still gravity fed.

Problem:
I believe the bike is starving for fuel because it dies a minute after riding (idles extensively) and starts back up after a few seconds of sitting. (The less time I wait before riding it on the quicker it dies, because i feel like the bowls aren't filling)
Also the carb and tank are positioned awkwardly, as a result the less fuel is in the tank the less pressure I have in the line, this creates a jarring inconsistency.
Current tank nozzle points away from carb.

Thoughts:
there has got to be some optimal fuel pressure (I imagine it is very little) where the bowls stay full but fuel doesnt blow past the needle and flood...

Ideal scenario:
Get the bike back up and running with fuel pump.

Current ideas:
Increase diameter of fuel hose, I feel like if I do this I'll lose pressure in the line faster as the tank drains but I'll have more volume at the ready.
Decrease diameter of the line, would increase the pressure, and It would probably maintain the pressure closer to empty.
Cut current tank nozzle off and weld new threaded bung for AN fitting potentially use one of those filtered petcocks and just have a one straight line from tank to carb. Creating less bottle necks and simplifying the journey the fuel has to make from tank to carb.

Future ideas:
I have taken thermodynamics I.
Spring 2019 I'm taking thermo II, and computational fluids. I have already started thinking about how to make this bike fuel injected. If I could properly design the manifold, I pretty confident i could machine it. Prototyping the fittment would be easy as I have a large 3D printer. Last year or so I have put about 100hours each on cnc and lathe. I have experience with programming so working with air and fuel sensor won't be too difficult.
Thinking about making this my senior design project. Not sure yet.
 

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Check you float valves. Carbs with fuel pumps typically have very small diamtere float valves in the 1.5mm range where bikes with gravity feed need much larger valves (2.5 - 3.5mm) to allow sufficient fuel to flow at lower pressure.
 

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you could not possibly be anything but a complete moron from another planet who is trolling us.
fer fucks sake you don't even know basic physical principles of gravity and whatnot....that exist on this planet
and you are an engineer ?? horseshit !! ,fuckoff ,go home and troll on your own planet asshole
 

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I cleaned the carbs, I have the floats set high high, so that the bowls can fill more. Fuel is still gravity fed.
... that might not work so well, fuel level is set to make the venturi pipe do it's thing :|

Problem:
I believe the bike is starving for fuel because it dies a minute after riding (idles extensively) and starts back up after a few seconds of sitting. (The less time I wait before riding it on the quicker it dies, because i feel like the bowls aren't filling)
Also the carb and tank are positioned awkwardly, as a result the less fuel is in the tank the less pressure I have in the line, this creates a jarring inconsistency.
Current tank nozzle points away from carb.
... you just confirmed why the bike has a fuel pump on it.

Thoughts:
there has got to be some optimal fuel pressure (I imagine it is very little) where the bowls stay full but fuel doesnt blow past the needle and flood.
... is totally dependent on your fuel consumption,
have you done anything to the bike to increase fuel consumption significantly like remove the entire exhaust system and or install pod filters :rolleyes:

Ideal scenario:
Get the bike back up and running with fuel pump. <- yaaaa! that or replace the fuel tank with something far superior.

Current ideas:
Increase diameter of fuel hose, I feel like if I do this I'll lose pressure in the line faster as the tank drains but I'll have more volume at the ready.
Decrease diameter of the line, would increase the pressure, and It would probably maintain the pressure closer to empty.
Cut current tank nozzle off and weld new threaded bung for AN fitting potentially use one of those filtered petcocks and just have a one straight line from tank to carb. Creating less bottle necks and simplifying the journey the fuel has to make from tank to carb.
.... Montesa 360VA had 2 fuel taps and 2 fuel hoses to feed one carb. ... needed both taps open on reserve or you could starve the 54mm Bing for fuel if you really, really worked at it.


btw: your fuel pump is on there to deal with a problem that manifests when the tank is low on fuel, if the thing lacks fuel pressure when your tank is full you have a problem elsewhere.
 

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... have you seen the ones with a secondary fuel tank that houses a fuel pump? The guys who designed that abortion were suppose to be engineers too!
 

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Discussion Starter #296
I cleaned the carbs, I have the floats set high high, so that the bowls can fill more. Fuel is still gravity fed.
... that might not work so well, fuel level is set to make the venturi pipe do it's thing :|

Problem:
I believe the bike is starving for fuel because it dies a minute after riding (idles extensively) and starts back up after a few seconds of sitting. (The less time I wait before riding it on the quicker it dies, because i feel like the bowls aren't filling)
Also the carb and tank are positioned awkwardly, as a result the less fuel is in the tank the less pressure I have in the line, this creates a jarring inconsistency.
Current tank nozzle points away from carb.
... you just confirmed why the bike has a fuel pump on it.

Thoughts:
there has got to be some optimal fuel pressure (I imagine it is very little) where the bowls stay full but fuel doesnt blow past the needle and flood.
... is totally dependent on your fuel consumption,
have you done anything to the bike to increase fuel consumption significantly like remove the entire exhaust system and or install pod filters :rolleyes:

Ideal scenario:
Get the bike back up and running with fuel pump. <- yaaaa! that or replace the fuel tank with something far superior.

Current ideas:
Increase diameter of fuel hose, I feel like if I do this I'll lose pressure in the line faster as the tank drains but I'll have more volume at the ready.
Decrease diameter of the line, would increase the pressure, and It would probably maintain the pressure closer to empty.
Cut current tank nozzle off and weld new threaded bung for AN fitting potentially use one of those filtered petcocks and just have a one straight line from tank to carb. Creating less bottle necks and simplifying the journey the fuel has to make from tank to carb.
.... Montesa 360VA had 2 fuel taps and 2 fuel hoses to feed one carb. ... needed both taps open on reserve or you could starve the 54mm Bing for fuel if you really, really worked at it.

btw: your fuel pump is on there to deal with a problem that manifests when the tank is low on fuel, if the thing lacks fuel pressure when your tank is full you have a problem elsewhere.
I will set the floats back to stock height. This will hopefully tell me if its a fuel pressure or float level problem.
I will take another shot at investigating why my fuel pump was overheating and shutting off. This is the only way I see to address the pressure issue, as per your comment.
Are there "self regulating" fuel pumps and stop and go depending on the pressure?
The one I have seems to run constantly unless fuel safety relay cuts it off. This is why I think it overheats, and shuts off

When you say "replace the fuel tank with something far superior." what do you suggest?

That Montesa 360VA is a pretty cool bike, quite the guzzler.
 

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Discussion Starter #297
Check you float valves. Carbs with fuel pumps typically have very small diamtere float valves in the 1.5mm range where bikes with gravity feed need much larger valves (2.5 - 3.5mm) to allow sufficient fuel to flow at lower pressure.


Good point I'll look into it.
 

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Set your carbs back to the stock fuel levels and fix your fuel pump issues. You still suck at diagnosing. I am pretty sure that your fuel pump has a set of contact points located in the base under a plastic cover. The cover collects moisture and corrodes the points set so they won't move. If the points stay closed, the pump runs continuously and overheats. Check your fuel pump.

You can't get a carburetted bike with a fuel pump to run correctly and you think you can successfully get it to run with EFI?
 
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... That Montesa 360VA is a pretty cool bike, quite the guzzler.
Yep, fuel tank holds 2 gallons of premix and if you are careful that's just enough to finish a 20 minute moto race.

What makes a good fuel tank imho: Aluminum construction because it is light weight and does not rust, capacity that is commensurate with your application, location and shape that facilitates gravity feed if you are running carburetors, and lastly ;) it should look really fly on the bike.
 
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