Aprilia Specific Specifications Wanted

[ZAMR]

Hey all,

Our team is switching to the Aprilia this year, as it seems a lot of teams are, so I was wondering if anyone would be willing to share the following information:

ConRod length
Wrist Pin offset
Port flow/discharge coefficients
Port duct geometry
Valve diameters
Valve lift or Cam profiles

This is our first year with the engine and don't want to open the case for reliability purposes. Any information would be greatly appreciated.

Thanks!

Zach Moorhead
Sooner Racing

[ZAMR]

Hey all,

Our team is switching to the Aprilia this year, as it seems a lot of teams are, so I was wondering if anyone would be willing to share the following information:

ConRod length
Wrist Pin offset
Port flow/discharge coefficients
Port duct geometry
Valve diameters
Valve lift or Cam profiles

This is our first year with the engine and don't want to open the case for reliability purposes. Any information would be greatly appreciated.

Thanks!

Zach Moorhead
Sooner Racing

[ZAMR]

Sorry, thats the 550cc RXV model.

[Erich Ohlde]

there should be aprilia engine manuals floating around the internet for all the sx/rx engines. they should give you some of the measurements that you want.

[michaelwaltrip]

well, for reliability purposes, it doesn't matter whether you open the cases or not. the engine is still going to give you problems. just ask KU, or Texas, or Auburn, or anyone else who decided it would be a good idea to switch to the aprilia. Remind me again how many teams running aprilias finished endurance? two? and one of them got dq'd afterwards.

sorry, i kinda got carried away there. i went through this fight with our team last year when they wanted to switch to an aprilia and i was really relieved when i turned out to be right about them. Erich, how many hours did you guys spend on the dyno just trying to get the thing RUNNING, much less tuning it?

but seriously, i hope for your sake that you have better luck than everyone else did, and i'm sure that an aprilia service manual or a dealer will have some of those specs for you, as long as you ask to speak to a mechanic.

[war eagle racer]

If you plan on switching to the Aprilia you will want to get a few starters. We went through at least 6 starters.

Every team that's going to switch the aprilia needs to keep in mind unlike the CBR the aprilia is a full blown race motor. You can't treat it like the cbr because if you do you'll have a expensive door stop.

even with all its short comings it's a great motor(If you get it to start); cbr doesn't even compare down in the low rpms

[Erich Ohlde]

We elected to add a cam sensor so we did spend a good amount of time messing around with that. I will say that splitting the case is a requirement if you don't want chocolate milk for oil. We haven't had any issues with engine internals except for one 3rd gear failure on the dyno. honestly the engine (when it is running) has been as bullet-proof as our f4i's. actually better if you consider that pretty much everytime we did more than take off a valvecover of the f4i we had engine problems.
the starters on the Ape's is terrible, even the new rewound superstarters don't last long.
I actually like this engine, but adding a cam sensor sucks.

[Kemper]

A little bit off-topic, but related to aprilia engine (I got curious, we are a first year team running aprilia too):

What is the issue with the starters? do they blow "naturally" (i.e. doesn't matter how good engineer you are, it will blow)? Or they blew because you did something that wasn't supposed to do? If you did something wrong, can you share what we shouldn't do? I don't think starters can get quickly down here in South Korea, so I guess we will have to order some in advance.

Another question:
I'm not an engine guy, but I like to play with moving stuffs. I was trying to shift gears with the engine turned off but it seems that it goes just 1st and 2nd, I don't feel it clicking the 3rd and on. And the clutch is kinda mysterious too: the pinion doesn't move freely with the clutch pressed. Should I apply more force on the clutch cable or am I doing something wrong? We still didn't run the engine, by the way. We want to figure this things out before we blow something =D

[michaelwaltrip]

i believe the issue is that the starters are undersized for the applications. from what i've heard, they don't even last long on the bikes.

[John Grego]

The starters wear out naturally fairly quickly. We ran into most of our problems on the dyno when you do multiple starts. Also, if the battery isn't fully charged the starter has a difficult time spinning the engine fast enough, (another good way to destroy an electric motor) so make sure you use a jumper battery or a something so that your battery is full. We didn't have many problems once we got our map figured out and the engine would start after only a second or two. Make sure you order extra.

You guys are going to have your hands full as a first year team and I would probably suggest going with a different engine on your first try...but there's something to be said for being ambitious!

[Didier Beaudoin]

We blew 3 starters before we changed the set of starter gears, and then we didn't blow any. Have you guys done the same thing? For us, it seemed to do wonders.

[Erich Ohlde]

I believe that starter part number was originally used on a 50cc scooter. not a good idea for a high compression 550cc.

the clutch won't work properly until the transmission oil is up to temp (i.e. it will drag until the tranny oil has warmed up, prolly 70-80 Celsius)

[Wesley]

Erich,

We did manage to get an '08, so we shouldn't have to open it up to fix the leakage issues.

The plan is also to limit starting times with a relay. I anticipate us burning through at least a starter as we get it to run, but I'm anticipating being OK with reliability once we get to that stage. I heard a lot of the Aprilia teams just crank on it for so long at competition, it's no wonder the starters gave up. If it doesn't try to go in the first 5 revolutions, something's up.

And Zach, we have the manual for the engine... it has a lot of those dimensions. Once we get ours in we can measure head geometry without pulling it apart.

But we DO need discharge or flow coefficients! If anyone is willing.

[ZAMR]

Wes, I tried looking in the PDF engine manual on our network drive. NONE of those measurements were in there. Is the hard copy manual a different manual altogether?

Zach Moorhead
Sooner Racing

[Brian Schien]

We burnt one starter and on sprage clutch, which I believe, caused our starter failure. It was missing a needle bearing witch is strange because we bought a bike with 500 miles and the motor was never apart it had to poor QC from the factory. This was all just getting the engine running on the engine dyno with stock wiring ecu exhaust and intake. We ran our car with stock ecu and used tune boy to tune it wasn't the greatest but we didn't get our engine till February and didn't have the time to get it running on motce but we will be on motec in 09 it ran very good on the stock ecu with stock tune with our intake and exhaust it only needed a small amount of tuning that we did on our chassis dyno in less that an hour. Some one mentioned limiting the staring time this is done on the factory ecu it limits it to five seconds than you must turn power off and on and try again. Our car always starts know since we got back from Detroit and its not so cold and damp. These things don't like temps less then 50 F

Jayhawk electrical what was wrong with your car on endurance day you guys burnt up both of the starters we gave you. Which reminds me I got a rebuilt one back from Tim but I still have the other one you guys burnt up I need to get it rebuilt.

We are picking up our 09 motor on Thursday so it we be time to start playing with the motec. If I could give any suggestions to a first year team with an aprilia is run it on a stock ecu if you have it you going to have lots of other problems this will just make it easer on yourselves

Brian
UNCC FSAE

[Erich Ohlde]

sprag clutch went south.
tim is in wisconsin for a vacation, i'll remind him that we still owe you guys a starter.