(Sorry, I do not know how to insert the photos into the text on this forum. If an administrator or mod wishes to do so, please feel free. I apologize for the clumsiness.)Important Note: (added May 19, 2010)
I had a problem with the cheap Chinese Airtex brand I originally installed. It stuck closed once and caused the starter to continue cranking after the engine started. I replaced it with a relay from the Ford dealer, Ford part number E9TZ-11450-B I highly recommend installing the Ford part in place of any cheap Asian part from the chain stores to avoid the problem I encountered.
Also note this Ford unit has no "I" terminal, so installation will be even simpler.
EDIT: Here is what I wanted it to look like:
http://www.southbayriders.com/forums...ad.php?t=91996
We all know aprilia starter relays are a very weak link on all their V990 bikes. Rated at 50 Amps, it is woefully inadequate for a starter that pulls over 200 Amps. The after-market offerings are not much better with 75 Amp ratings.
I vowed when mine failed, I would upgrade to a heavy duty Ford unit that can withstand well over 500 AMPS on any given Sunday.
Mine failed a couple days ago at 43K miles. It had been weak for awhile with a 3-volt drop causing only 7 to 8 volts to reach the starter with weak cranking. The contacts heated up enough to partially melt the rubber boot on the output lead.
I decided to take pics after I had already removed the old relay and cut the leads. Sorry, but here's what I have:
The empty cavity with relay removed:
http://www.apriliaforum.com/forums/a...1&d=1266778758
Good idea to start off with a good schematic, thanks to Carl McNamee for the Futura shop manual on PDF.From this, I learned the red lead at the relay is battery power from the ignition switch while the blue one is the relay ground coming through the sidestand and neutral safety switches.
http://www.apriliaforum.com/forums/a...1&d=1266778758
I used an after market Airtex brand Ford starter relay, part number 1M1090, any brand will do. I pulled this number for a 1988 F-150 5.0 liter application, but any relay from a Ford vehicle from the sixties all the way up to the nineties will work. The two small terminals are marked "S" and "I" on the ford relay. The "S" is the start input signal from ignition switch where our red lead of the old relay harness will attach, the "I" is an ignition output we will not use.
This relay cost me USD $12.00 wholesale, retails around twenty bucks.
http://www.apriliaforum.com/forums/a...1&d=1266778758
Here's the old relay after I already cut off the harness connector and began attaching connectors. Cut it off close to the relay for maximum length to work with, then throw that piece of shit in the rubbish can where it belongs.
http://www.apriliaforum.com/forums/a...1&d=1266778758
Here is the old next to the new. Big difference.
http://www.apriliaforum.com/forums/a...1&d=1266778758
Here is the wire prep, a small 4 or 5 mm heatshrink eyelet on the red lead to attach to the "S" terminal of the new relay, and a larger 6mm plain eyelet soldered to the blue lead for the sidestand/neutral safety switch ground circuit.
http://www.apriliaforum.com/forums/a...1&d=1266778758
The Ford relay must receive a ground signal to work, just like the aprilia relay. Difference is, the metal relay base must be grounded. Here I have attached the red lead to the "S" terminal, and bolted the blue lead to the relay base using a short 6mm bolt and locknut. By wiring it this way, the safety switch features on the bike are still 100% retained. Were the base simply grounded to battery negative, all safety functions would be bypassed. Don't want that.
http://www.apriliaforum.com/forums/a...1&d=1266778758
The factory aprilia battery positive and starter leads have 6mm eyelets on them, and our new relay has beefier 8mm terminals. A simple reamer takes care of that issue.
http://www.apriliaforum.com/forums/a...1&d=1266778758
This is the final installation. With the "S" terminal at 9:00 o-clock from this view, the battery positive is attached at 12:00 terminal, while the starter lead is at 6:00. The modified relay harness plugs directly into the factory wiring harness.
http://www.apriliaforum.com/forums/a...1&d=1266778758
When I thumbed the starter, it spun so fast that the bike fired up before I could listen to the new cadence!I put it in clear-flood mode by opening the throttle wide and cranking for ten seconds. It did not skip a beat, cranked fast and glorious, has never cranked this beautifully in over 25,000 miles I've owned it, and the new relay has a deliberate and authoritative "thunk" when engaged that is music to my ears.
Oh yeah, time to sit back and relish a mod well done.
http://www.apriliaforum.com/forums/a...1&d=1266778758
This mod will work exactly as described for any motorbike that utilizes both power and ground triggers to activate it. Caution must be used when mounting it though. Futura gives me the luxury of a lot of space above the battery with all plastic, no metal frame for the relay to contact. If your different bike has metal nearby, care must be taken to not allow the relay base to contact any metal part of the bike as this could provide an unwanted ground to the relay that will allow it to bypass all the safety switches and crank over anytime.
DO NOT MOUNT THE FORD RELAY TO ANYTHING METAL!
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