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2018 Aprilia RS4 50 Euro 4 Upgrade Project

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Berkeley
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Re: 2018 Aprilia RS4 50 Euro 4 Upgrade Project

Post by Berkeley » Mon Oct 15, 2018 1:43 pm

kaldis12 wrote:
Mon Oct 15, 2018 10:43 am
Thats fine :D but if you remove the restrictor and jet it up correctly( bigger jets) you will end up with a littlebit better performance on the stock cylinder, but on a bigger cylinder this would have a hugggeee effect on how the bike runs. Experience with it how is your bike reacts to bigger jet(without restrictor) and if you get better performance then keep it but if its the same just put it back because bigger main jet means higher consuption( i dont know how much it matters on these small carbs, but on bigger ones its pretty noticeable.)
Great will do.. On another note on the way back home for some reason it just cut out whilst riding and wont restart. When the starter button is pressed it just clicks once but doesn't turn over.. seems like its an electrical problem maybe???? any ideas before I take her apart? thanks
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toratora
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2018 Aprilia RS4 50 Euro 4 Upgrade Project: Levers and discs

Post by toratora » Mon Oct 15, 2018 4:49 pm

The clutch lever looks amazing.

It sounds like the battery has a very low charge. The Ducati charging systems in these bikes are rather anemic. At the best of times they will charge up the battery enough for a start or two. Usually they don't even do that so well—especially if you employ an exotic lithium battery. I basically GP start my GPRs all the time. It's really not a big deal, but I can see how it might be challenging for a new rider at first. Still it's a very valuable skill to learn.

I can't remember what the disc is for exactly, but it's technically not a restrictor—even though it looks like one. I think I read about it sometime ago probably on Moped Army. Since you intend on adding a BBK I wouldn't worry so much about this carb, as you'll have to replace it once you start modding the engine. Just make sure all the fittings are in the proper place, and you should be fine.

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Re: 2018 Aprilia RS4 50 Euro 4 Upgrade Project

Post by kaldis12 » Mon Oct 15, 2018 9:18 pm

If I remember correctly that little plate is for better airfllow,(just like at the manifold) but its technically a restrictor as it blocks the air way and just forcing through that little hole.
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Re: 2018 Aprilia RS4 50 Euro 4 Upgrade Project

Post by Berkeley » Mon Oct 15, 2018 11:13 pm

Sooooo.. reading and watching you tube vids on the starting problem. I cant see how its just the battery. Why would the bike suddenly die when decelerating and not start up again? The battery is on charge so will try later but if the relay/solenoid clicks then the battery is meant to be good and the secondary wire connections are good also ( i believe).

The next thing i guess to try is the starter motor with a direct connection to the battery to rule out any secondary wire connections that could be stopping the bike from firing up. My hunch is that the stater motor is fooked. I had the problems a few days ago with it suddenly dying .. so maybe that was the precursor to it? but would a faulty starter motor cause the bike to die when decelerating???
any thoughts guys?
cheers
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kaldis12
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Re: 2018 Aprilia RS4 50 Euro 4 Upgrade Project

Post by kaldis12 » Mon Oct 15, 2018 11:38 pm

There should be no relation to the starter motor. If you decellerate and it dies it should be fuel related.
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Re: 2018 Aprilia RS4 50 Euro 4 Upgrade Project

Post by Berkeley » Wed Oct 17, 2018 2:34 am

Hi, I checked the battery. 13 volts,

pressed the starter button it nothing happened, relay just clicks.

Image

Joined the wires at the back of the relay, pressed the button, only clicks again

Image

Took off the relay and connected the wires at the front of the relay.. pressed the button nothing happened. So its defiantly the stater then or something else???? thanks

Image
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Re: 2018 Aprilia RS4 50 Euro 4 Upgrade Project

Post by kaldis12 » Wed Oct 17, 2018 2:36 am

Ohh i see so you cannot start it up. If it doesnt turn over then something is with the starter motor. Connect the starter to a direct 12v, if it spins up then its good, but if its not then you propably need to change it up.
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Re: 2018 Aprilia RS4 50 Euro 4 Upgrade Project

Post by Berkeley » Wed Oct 17, 2018 4:39 am

yeah i hooked it up directly to the battery and nothing happened, then i hooked it up to a mains 12v supply and nothing. so its for sure dead. Will i need to drain the oil when i take off the starter motor? ie oil pisss out everywhere? thanks
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Re: 2018 Aprilia RS4 50 Euro 4 Upgrade Project

Post by kaldis12 » Wed Oct 17, 2018 5:10 am

No because the starter is outside of the engine and only goes to the ignition. If Im right.
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Re: 2018 Aprilia RS4 50 Euro 4 Upgrade Project

Post by jkv357 » Wed Oct 17, 2018 7:16 am

Check the voltage as you push the button.

Just because the battery will hold full voltage doesn't mean it is good. Only way to know is to test under load (cranking).

When you hit the starter the voltage should stay over 10V. If it drops below that you have found the problem.
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