Hi Guys

I am new here, been at RGV and Aprilia forums for the past 6 odd years (hence the user name), raced mc18 & rgv's in 250 proddie 10-15 years and now have an Aprilia Rs250 in Stage 1 kit trim for F3 here in NZ.

Anyhow, i have recently picked up an MC21 and really enjoy it, pretty keen on getting full power and throttle response out of it. As such i did the orange/blue wire to black /white wire splice with disasterous (spelling?) results.

As soon as i turn on the ignition switch it blows the 15a fuse. I double checked the wire colours and is correct.

Anyone have any ideas what i may have done wrong?

To be honest i DID cut the black wire but used a bullet connector to rejoin, I struggle to see that as the cause but i am sure you guys could clarify that for me too....?

Cheers

Mark

Hi Mark, and welcome to the Forum.

Check out the MC21 wiring diagram in the Workshop section to see what the splice actually does.

It sounds like you may be splicing the "wrong" end of the orange/blue into the black/white wire. In standard form, the O/Bu wire goes to earth (ground), so when you cut it you need to splice the end at the PGM connector to the Bk/W.

If you splice the O/Bu at the harness side to Bk/W you will create a dead short, and that will blow a fuse.

I hope that makes sense...
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Hi Andy

Cheers for the welcome!

I think i know what you mean, i did the splice about 4 cm's from the PGM box, on the black plug.

Is this correct?

Mark

Actually i just rethought that, i may have got the right idea now.

Is the loose end of the orange wire the harness side and NOT the PGM side...?

Mark

Yes, but did you splice the end of the O/Bu wire coming out of the plug, or the end left poking out of the harness?

You CUT the O/Bu, but you splice INTO the Bk/W. If you have simply joined the two wires, or spliced the Bk/W into the O/Bu, then you will get a short... (and we all know what Shorties lead to!)
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Andy.
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Thanks Andy, you were right i had connected the wrong end of the orange wire!

Going now, runs really well but feels a little woolly through mid range at full throttle, not really crisp like it should.

Is that the main jets or should i look elsewhere?

Cheers

Mark

Have you drilled the airbox?

2 x 20mm holes in the lid (on the front slope, where the sticker is) will do it. 4 holes are better, and then you can always tape 2 off if you need it a bit richer one cool damp day/evening without having to get into the carbs and change jets!
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Andy.
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Thanks Andy, i did the Tyga cut on the back of the airbox. Is that an equivelant?

It didn't really make a difference though.......


Mark

Ive cut 4 holes in the front section of the box.
If feels great up top, but feels worst mid range
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You'll need to rejet.