Restarting the original

discussions specific to the 750 Paso

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enginerd
Posts: 53
Joined: Fri Jun 25, 2021 3:18 am
model: 750 Paso
year: 1988
Location: USA

Restarting the original

Post by enginerd »

To start this off, forgive me for any ramblings and out of sequence thoughts or progress through this project. I've got a few years to catch up on since I acquired this bike.

Firstly, I'm Brian and I'm a motorcycle addict...

phew, that felt better. :lol:

Wanted to post this up here but it was just over 3 years ago I was lucky enough to purchase Mike's pristine '87/'88 750 Paso. I've known mike for nearly 20 years now it seems as I met him through VW's. Mike helped me out when I bought my first bike, a '95 Ducati 916 14 years ago. In a sense we've always enjoyed the same cars and motorcycles.

May/ June of '21 Mike and I were talking about he mentioned about needing to find a home for his Paso as he doesn't have the time to get it running for the street after sitting for so long. Given my knowledge and tools for working on a bike, I was interested; plus it was in perfect condition being a display piece for a number of years. It was then I make the journey down to Sacramento with a trailer on my VW to pick the bike up. Drove from Portland to Sacramento with a side trip to Reno briefly. Spent the night, loaded the bike up and headed back north to Portland in the morning.

Here's a few photos from loading up and the return trip. I've got many MANY entries to write but just wanted to get something started.

Sitting and waiting for me
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Waiting to load up
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I think I've got it strapped down enough ya think? 10ish hours back home.
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enginerd
Posts: 53
Joined: Fri Jun 25, 2021 3:18 am
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by enginerd »

Bike and trailer weight for the drive home
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The Paso has landed! nice little spot for the bike to sit for a while. Just had to rearrange my motorcycles to fit this one in now.
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Oh and do you recognize and guess the garage paint theme? :wink:

I like bikes....
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Finally getting around to working on the bike just over a year ago. Time is my enemy, I've got lots of cats and work too much. Merely collecting my retirement projects, haha. Ok, not anywhere near that age but I figured by the time I get them finished, I'll be that age to retire.
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enginerd
Posts: 53
Joined: Fri Jun 25, 2021 3:18 am
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by enginerd »

Checked out the fuel tank for it's condition and everything looks good, even used my scope to view to view the inside and it looked great. Nice and dry despite having the hint of gas from sitting all those years.
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OEM Weber carb pulled for a rebuilding
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enginerd
Posts: 53
Joined: Fri Jun 25, 2021 3:18 am
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by enginerd »

All four valve covers needed a serious scraping to remove the old paper gaskets. New aluminum ones have been put in place.
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Cleaning the intake with my ultrasonic cleaner. Cleaning agent in Crystal Simple Green mixed on the strong side, works wonders!
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enginerd
Posts: 53
Joined: Fri Jun 25, 2021 3:18 am
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by enginerd »

All valve covers nicely cleaned up, finally.
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Let's get a new timing belt going on here now how abouts...
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New belt on the top, old on the bottom
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enginerd
Posts: 53
Joined: Fri Jun 25, 2021 3:18 am
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by enginerd »

Bench top garage computers are so helpful for times like these.
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Even bought the right tool for this because as an engineer, there are numbers in a spec for a reason so I should follow rather than learning the "feel" the hard way. One thing about using this tool, I had to do a lot of research to where it should be used and what frequencies are to be read and where. I ended up using the 5-6mm allen key method after seeing the variance of the frequency at certain points on the belt between the rollers. This tool will come in handy when I do the belts on my 916 at least.

I believe it was Gerhards post about where to measure the frequency and fitting the 5mm Allen through that convinced me to bail on using the tool at the moment.
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Mc tool
paso grand pooh-bah
Posts: 1974
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: Restarting the original

Post by Mc tool »

Your mufflers look a lot like mine ( I like them :) )
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You can drop a golf ball right thru them so I dunno so much about calling them silencers ( nearly emptied a bank in Chch when it backfired in the carpark :lol: :lol: )
I wish I was young again............Id be heaps smarter than last time
enginerd
Posts: 53
Joined: Fri Jun 25, 2021 3:18 am
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by enginerd »

Ah yes, the mufflers. They're the Staintune ones that Mike said are super loud so I can't wait to hear them!

On another note, I heard earlier this year that the size tires I needed were back in stock. Bought a rear tire on a whim and just last week picked up the front tire. Rear and Front tires were made 1722 and 1122. I at least have new tires. The rear tire on it is stamped 1400 and the front I can't immediately find. I'll just say both tires are just cracking apart.
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Mc tool
paso grand pooh-bah
Posts: 1974
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: Restarting the original

Post by Mc tool »

Mine are NZ made Cycleworks , They are well made ..... drill the rivets out to remove end cap for repacking and fitted up well . I fitted them at my place of work and when I cranked it up one co worker said that he had never heard a bike that sounded like that and went and bought a 900 monster ( not straight away )
I wish I was young again............Id be heaps smarter than last time
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englishstiv
paso grand pooh-bah
Posts: 1117
Joined: Wed Apr 09, 2008 9:57 pm
model: 907 I.E.
year: 1992
Location: Manchester, England.

Re: Restarting the original

Post by englishstiv »

Over the many years on this site I have enjoyed reading these sort of running restorations and rebuilds. Since joining hopefully you have been able to delve into the archives and seen the amazing wealth of knowledge that we have on here so keep it up and I look forward to seeing the photo's of you breathing life into those pipes.
DUCATI 907ie 1992
HARLEY DAVIDSON ELECTRA GLIDE CLASSIC 1991
Ducati Streetfighter 955 V2
enginerd
Posts: 53
Joined: Fri Jun 25, 2021 3:18 am
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by enginerd »

Small update here.

Over the weekend I went down to California to visit my friend I bought the bike from. From this trip I picked up the rebuilt Weber carb for it and it just looks amazing!
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One thing about the carb. While it was being rebuilt, it was discovered that a support inside, I believe for the float bowl was broken. Scoured the Ebay and picked up another used Weber carb from a Paso for a steal. Why did I go with the Weber you may ask? Currently the bike is set up for this and my goal right now is to get the bike rideable for minimal cost but done right. Later I'll probably upgrade them but for now, let's just get it going.

After I installed the carb that was rebuilt, I realized that the upper intake that came with it was from a different Paso (It wasn't labeled which model it all came from). Missing on the newer manifold was the vacuum line ports. Now I just need to put the original piece back on and then I can start hooking up the hoses and seeing what ones there need to be replaced.
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As the weather gets colder, work outside is becoming less and less so this is how I spend my evenings at times. :lol:
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Mc tool
paso grand pooh-bah
Posts: 1974
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: Restarting the original

Post by Mc tool »

Re the vacuum ports .... there is one for the weber marelli ignition module , but I think some of the 750's used Koukusan modules that didnt req a vacuum port . Im pretty sure there are a couple of ports for balancing the 2 venturis ( use throttle bypass screws ). Dunno if any Paso variant came with a vacuum fuel pump but a few peeps fitted a Monster vacuum pump in an effort to get the weber to behave .
Search here for " Weberology "
I wish I was young again............Id be heaps smarter than last time
murphus
Posts: 106
Joined: Wed Jun 24, 2020 6:27 pm
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by murphus »

Re Re the vacuum ports ... on my '88 Paso there's no port at the rear as on yours and where you have a port on the right side on mine there's a nascent hole but it isn't drilled through or threaded. Was that a California emissions thing? And if so, what do the ports feed/pull?
1973 BMW R75/5
1976 Suzuki GT185
1983 Lavarda RGS 1000
1988 Ducati Paso 750
1995 BMW K75
murphus
Posts: 106
Joined: Wed Jun 24, 2020 6:27 pm
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by murphus »

I take that back; faulty memory. The right side port is threaded but plugged on mine.
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1973 BMW R75/5
1976 Suzuki GT185
1983 Lavarda RGS 1000
1988 Ducati Paso 750
1995 BMW K75
enginerd
Posts: 53
Joined: Fri Jun 25, 2021 3:18 am
model: 750 Paso
year: 1988
Location: USA

Re: Restarting the original

Post by enginerd »

On mine, the tiny port is for the ignition module (yay old tech) and the side ports, I can't immediately remember off the top of my head. When I removed the braided line that was on there, it was cracking and twisted and I just removed it but saved it because well, something inside me said I should until I get it running. The only fuel lines that really got shredded were the ones trying to remove the Y connector that had the carb jet in it. That's a whole other topic and section of this build.

Oh, before I forget with the fuel lines, they're 7mm braided right? I got a few feet and they seem to match; given time and dryness/ stretch but I can't confirm it anywhere. 8mm seemed to be the standard for a few bikes but again, nothing for sure that links me to these bikes.
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