2000 Aprilia Pegaso

Put about 60 miles on it this weekend!  The first thing I noticed was that the lowering link was letting the tire hit the rear fender, and it chewed through the rear turn signal wiring:  

That's a big fail, and the bike came with the stock links in a bag so I swapped those out:  

Raised the front to match and went for another ride:  

It was great!  Other than a little overheating, the bike was well behaved.  Looks like the radiator cap isn't letting coolant back in, so I drained and flushed the coolant and ordered another cap:  

Didn't stop me riding it to dinner, though.  I just need to make sure to keep the coolant topped up since it won't draw from the overflow tank until the cap is replaced.

The only other little issues I encountered (and fixed) were the battery clanking around and one of the mufflers being loose.  And the headlight is terrible, which I don't have a solution for yet.

Battery took a dump.  Replaced it.  Replaced radiator cap too, still not pulling from the overflow when it cools down.

Bike is still awesome other than that- I've been refilling the cooling system by blowing into the coolant overflow like a bagpipe before I start the bike, which I'm sure anyone who has seen me in a parking lot has enjoyed 

It has been getting 40-45 mpg, which could probably be better but it runs great so I'm not complaining.

Noticed some bubbles in the coolant- these engines are known for head gasket issues.  Hmm, what else has an aluminum engine with notoriously garbage head gaskets and a factory recommended bandaid?

Dumped it in, went for a brief ride to circulate it:

Hopefully it helps.  If not... who cares, $400 Aprilia!  Gaskets are cheap anyway.

Pablo went on a pretty decent day trip last weekend with some friends:  

It was a mixture of paved and gravel twisties and this bike is pretty perfect for that.  The pace wasn't super fast and I had no overheating issues, but the bike DEFINITELY has a blown head gasket.  A pretty benign one, but the bubbles in the coolant reservoir every time the bike is ridden hard don't lie- I'll need to replace it at some point.

Tore things down a bit to retorque the head bolts:

Mostly easy, although I really hope whoever put the rear valve cover bolts under a motor mount has gotten past whatever terrible thing in their life caused that to seem like a good choice.

Look at how wacky the valvetrain on this thing is!  5 valves, skewed cam lobes, and one screw adjusted rocker arm while the rest are shim and bucket:

Retorqued the head bolts to 40ft-lbs and found two of the four to be a little loose.  Reassembled, went for a ride:

Still blows some bubbles into the coolant if you romp on it for a while, but totally rideable as it sits.  I'll track down a good gasket and plan to tear into it some weekend.

Looks nice and clean top side with the exception of that crazy valve train configuration.  That's nuts! 

Head gasket should be simple enough for you to handle.  

¯\_(ツ)_/¯ said:

I'll track down a good gasket and plan to tear into it some weekend.

I'm not very patient, so "some weekend" is now.

First hurdle- Alaska was not kind to the exhaust studs:  

Removed by hammering on a smaller socket, some fared better than others:  

Before long most stuff was removed:  

I can't get over how wacky these cams are:  

Then I fought with the head for an embarrassing amount of time- hours, in fact, before I discovered this one tiny bastard of a bolt hiding behind the starter.  It goes up, instead of down like EVERY OTHER FASTENER on the head, and was caked in so much front wheel schmoo that I couldn't see it:  

With that gone, I could lift the head up slightly, prop it with a couple of spray can caps, and remove the studs with some channel locks:  

With the studs removed, the head was able to come out of the frame:  

Some cleaning and a little filing to remove gouges I put in it when prying the head off:  

Put the old gasket in the "window of shame"

And the new one on the block:  

Head is a tight squeeze when trying not to hurt the new gasket:  

And... installation is the reverse of removal or whatever.  I don't know the torque sequence so I did everything in a star pattern and went three passes of 20/40/42ft-lbs on the studs.  This is how it currently sits, waiting for me to get the carbs, exhaust, starter, and various coolant lines back on it before I can see if I actually fixed anything:  

Put it back together some more, ran it like this to make sure everything is ok and bleed the coolant:

Success!  Everything works so I put it the rest of the way together, put new brake pads on, and rode it:

It needs some little things here and there but so far so good I guess- no overheating at least, although I still see some bubbles in the coolant which I'm hoping are just residual from filling it.

Pretty good birthday present

A little exhaust sealant here:

Some fuel sealant there:

And some rtv on the cam chain tensioner and we're back in business.  Rode down this extremely loose railroad bed without issue:

I think I'm still under $900, even with the pricy OEM head gasket.

Yesterday I patched up some wiring and fixed the heated grips as well as I could without taking the whole system apart- they now work on "low" but are so hot that I can't imagine needing "high" anyway.  I'll call it a win!

Pablo picked up a cotter pin in the rear tire on the way home today:

Not sure when it got in there, but I made it home before it got totally flat.  Stupid thing:

Luckily I had a spare tube, so I swapped that out (at the expense of my fingers, that is a really stiff tire) and plugged the tread for good measure.  I'll make sure it holds air overnight but I'm pretty sure it's fine now:

Well, the fuel sealant tried its' best but Pablo has begun leaking from the corner of the tank again.  I need to find a tank that hasn't seen as much abuse as this one (so literally any other used tank) but pickings are slim- I see one in the UK and one in Italy on eBay, I made offers so we'll see what happens.

About 2 weeks ago, my $50 offer to some guy in Italy was accepted and a used tank made its way across the Atlantic:

The last of my black and green plastidip:

Some draining and parts swapping:

So far so good with 3 gallons in it, if there's not a puddle in the morning then Pablo is back in business:

I got about one mile before fuel stopped flowing- looks like the Italian version had different vent line positioning- so I pulled the seal off the one connection under the fuel cap and rode around for a while.  Fixed!

So for anyone wanting to use a European tank on your North American Pegaso, just pull off that little rubber thing in the picture, make sure the left side vent line is clear, and you should be good to go.  In theory it might leak more fuel when tipped over but it's not exactly like it stayed dry in that scenario before.

Pablo made it home from delivering Betsy to DC with no issues today, the longest ride I've attempted:

The charging system has a little trouble keeping up with heated gear, so in the future I'd like to go to LED lights to save some wattage, but for now I can keep playing the "do I want highbeams or heat?" game.

Nice thread! 

Saw a video about it and i needed to compare notes. It’s in french but pretty straight forward and self explanatory

Would you mind telling me where you bought your head gasket? thanks! 

otherwise there is an entire forum dedicated to the pegaso: pegaso.fr 

video below (there is also a carburetor adjustments one in the same channel )

https://m.youtube.com/watch?v=9ogDkJuK7AE

In reply to Flyingwheel :

I ordered my head gasket from AF1 Racing- it wasn't the cheapest, but seems to be high quality and has had no issues so far.

Cool! Thanks for the reply.

do you think there is a quality difference (significant one?) between these gaskets? I saw some in england for about $35 / $40. I’d be curious what the difference would be between an $80 gasket and  $40 one...i mean it’s just a gasket but i dont know

other question is, how hard was it to remove the top? Cause almost everywhere else i looked - including an entry in the french forum, they say you have to remove the engine from the fram... so i’m truly curious whether the engine has to be removed to do this or not? Thanks for sharing your thoughts

The one i found

https://www.ebay.com/itm/Aprilia-Pegaso-650-Garda-2000-Athena-Cylinder-Head-Gasket-/303054369870?nav=SEARCH

and this is my pegaso:

http://www.pegaso.fr/viewtopic.php?f=10&t=895

In reply to Flyingwheel :

Honestly I have no idea about the quality of the gasket you posted- I know that there was a revision to the OEM Aprilia gasket which was designed to stop whatever issue caused most of the warranty claims in the first place, and wanted to make sure I got the latest one since I didn't want to be in there again any time soon.  To me the price difference was worth it.

You don't have to remove the engine to change the gasket, but you will have to do some fiddly raising/lowering of the head onto the block so that you can unscrew the head studs.

Cool

curious, when you put the head gasket in, you didn't use or put any paste or anything? I don't see any but want  to confirm

i'm replacing the head gasket too

thanks!

In reply to Flyingwheel :

Nope, I just installed it with both surfaces as clean, dry, and flat as I could get them.

great thanks for the reply.

how many miles would you say you put on the bike since the gasket change?

I'm about to engage on this adventure, I'll let you go how it went,

I'll take some pics too. it ll perhaps help other people

thanks!