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'77 R75/7: Build/Restoration Thread  

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Mario Reznik
(@odontologist)
Active Member Expired Membership

A gracious HOLA to all members.

I am a recent member and this is my first post. I am the very lucky recent owner of a 1977 R75/7. It's a non runner.
My mission: to restore this iconic motorcycle to its full and proper working glory....and to go go where others have gone before.
My question: Where is the best place to start a "restoration" thread that I can use to log progress, ask questions, and post pickies?

Looking forward to chatting soon.

Mario
Umina Beach NSW
Australia

Quote
Topic starter Posted : 05/14/2020 04:16
Scot Marburger
(@8166)
Member Moderator

Sorry for the delay in approving your first message, Mario. It was under the wrong topic, and nobody saw it. 😉

I've answered your question to moving your post to the Wrenching topic. You'll be doing a lot of wrenching as you get your bike back to road worthy...

ReplyQuote
Posted : 07/07/2020 19:55
Richard Whatley
(@wobbly)
Member Moderator

Welcome Aboard !

With apologies to NASCAR.... "Gentleman, start your engine !" Right here...

😛

[color=blue]Don't hide 'em, Ride 'em !!
#15150[/color]

ReplyQuote
Posted : 07/07/2020 20:56
Mario Reznik
(@odontologist)
Active Member Expired Membership

Ok, back online, so let me say a few things about myself.

I do like pina coladas, and getting caught in the rain......oops. Wrong website.

This Cuban classic in Havana Gold is pretty much complete except for the mirrors. The following is a short list that will definitely need attention:

Brake systems, forks, rear shocks, steering, wheels and tyres, stands, electrical unknown as I'm yet to hook up a battery.

The engine leaks oil, with the pushrod tube seals looking likely culprits, but who knows where else. The carbs will get opened, cleaned and revived.

As soon as I figure out how to attach more than one photo to a post, I would like to show more, but for the moment, one it is. If anybody can help out with this function, I will be grateful.

Here a picture of my machine. You will notice that, as an Australian delivered vehicle, the steering is set up for left side driving.

 

ReplyQuote
Topic starter Posted : 09/14/2020 02:45
Richard Whatley
(@wobbly)
Member Moderator

Mario -

1) The place to start is to get the bike, as it currently sits, to run. This may require you to buy the necessary tune up items and rebuild the carbs, but you'll probably be well under $100. The reason for this is that VERY first step is to make sure you have something worth rebuilding. You do NOT want to end up with $10,000 invested in a bike you can only sell for $2000. In other words, you want to start with a bike that doesn't need a huge investment up front. There are too many 1970-something bikes out there in great condition to get stuck with one that needs 5 years and $8000 just to get the first ride around the block. 

Take it from me, the best way to do this is to ride while you restore. This will keep your interest and commitment level way up. Otherwise, you'll soon loose interest and move onto other projects. 

2) Secondly, as a sub-part of #1, this requires that NONE of your restoration steps disable the motorcycle for longer than 24 hours. In other words... DO NOT begin by taking the engine out of the frame. That's a huge beginner mistake. Those bikes hardly see the light of day ever again. It's too big of a "bite". Take small "do-able" bites like the front wheel. Install a new tire, new brake shoes, and then lube the wheel bearings and cables. Then go for a ride. The following week, attack the rear wheel in the same way. This allows you to stay focused on small tasks, and keeps you from feeling overwhelmed.

Hope this helps. 

[color=blue]Don't hide 'em, Ride 'em !!
#15150[/color]

ReplyQuote
Posted : 09/14/2020 12:48
Mario Reznik
(@odontologist)
Active Member Expired Membership

Thanks Richard. Some very sound advice. I actually read your sticky at the beginning of this forum on getting the bike on the road. It makes sense. I did some basic costing from my preferred provider in Western Australia - Munich Motorcycles. Consider this a plug. No interests on my part. These people have looked up the meaning of the term "service".

To get the bike on the road to an acceptable safe level....

Carb parts, spark plugs, fuel hose $160, Caliper kit $50, with piston extra $100, front brake line $120, Master Cylinder kit $200 or exchange $300, Fork seals and other bits and oil $50-100, new tyres tubes and tape $400 and that’s me fitting and balancing them, battery $200, and unknown other electrical issues unaccounted for at this stage, oil $40, Roadworthy certificate $40, registration and insurance $300.

Total conservative to get on road AUD $ 1500-1700 ( USD $ 1100 – 1200 )

So during the website freeze, I ordered some carb parts, dis-assembled them, cleaned them, new rubber bits, seals, mixture springs, float pivot pins and the are now back on the bike.

 

Before I proceed to do all the above, I will clean and adjust points, new plugs, oil and use a car battery to attempt a start to see if it does indeed start.

Question: Bing 32mm carbs (type 64). Left carb slide needle was in to fourth notch. Right was in to 2nd notch. I replaced them as I found them. Is this common or should the be at same stick-out?

 

ReplyQuote
Topic starter Posted : 09/15/2020 03:27
Richard Whatley
(@wobbly)
Member Moderator
Posted by: @odontologist

Question: Bing 32mm carbs (type 64). Left carb slide needle was in to fourth notch. Right was in to 2nd notch. I replaced them as I found them. Is this common or should the be at same stick-out?

• It is very common, but it's a common tuning issue that makes the bike run very poorly. To run smoothly, each cylinder has to pull equally, that is to say they need to be tuned identically. On most bikes, say with a Mic or Amal carb, you can easily see the needle groove and make sure the needle positions match. On an Airhead you need to measure the length of needle exposure (as it extends out of the slide) which takes more effort. Therefore, it's often overlooked. Good catch !

• It is also a common mistake to assemble the wrong enrichening disk into the carb body. This is one reason we suggest you disassemble one carb at a time. There are mirror image L and R side choke plates under the tiny side cover. On some models these plates are marked "L" or "R". There are other "one sided" parts, so keep an eagle eye on what you are assembling. The Bings look as simple as the balance of the bike, so owners let their 'guard down' and suffer the consequences.

• On a /7 with front disk brakes, the first place to look for electrical issues is the "mini cube" starter relay. Leaking (under-tank) brake master cylinders puke corrosive brake fluid all over the relay and its contacts. What you don't realize is that all power for the bike (except for the starter motor) passes through those relay connector contacts. That's why the starter relay generally needs replacing and the connector contacts need a GOOD cleaning. A "duel 87 relay" will cost you about $8 on Amazon. 

• Since you will eventually do extensive brake system repair and spend some money on a paint job, this is the perfect time to research DOT5 Silicone brake fluid. It is not supported by BMW... but then neither is the Aussie brand of DOT4 you intend to use !! DOT5 Silicone cannot be mixed with DOT3 or 4, so a complete system overhaul is the best time to consider it. It is NOT corrosive and will NOT eat up your electrical contacts or your paint as DOT4 will. It doesn't require annual service, but stops as well as DOT4. There is also some evidence that brake parts last longer when using it. I've been running it in Lockheed, ATE and Brembo systems since the late 70's without issue. It's one big disadvantage is DOT5 Silicone can't be used with ABS brakes, but Airheads don't have those. [Do not confuse this with DOT5.1 which is entirely different.]

Hope this helps.

[color=blue]Don't hide 'em, Ride 'em !!
#15150[/color]

ReplyQuote
Posted : 09/15/2020 15:36
Mario Reznik
(@odontologist)
Active Member Expired Membership

Both the relay and the master cylinder look in bad shape from attack by the corrosive fluid, so I will definitely be looking at the Dot 5 solution. Thank you.

Took the front cover off to show the distributor and points. Distributor looks weathered, but I am counting on these units to be hardy. I checked and adjusted the points using a clever tool that I bought over a year ago from a kind gent whose name I've forgotten, although I'm certain he is known around these parts. Trick for young players - after setting cam at points open position, and once advance unit is off, don't turn the crank or you will lose your timing mark. I fell straight into it, and I'm not so young. Anyway, reset the static timing on the flywheel and replaced the advance unit at open points position. Hope this is right.

One step closer to a potential start.

 

ReplyQuote
Topic starter Posted : 09/18/2020 03:02
Richard Whatley
(@wobbly)
Member Moderator
Posted by: @odontologist

Took the front cover off to show the distributor and points.

• Best practice is to disconnect the battery before removing or installing the front cover so that you don't burn up the rectifier, which is the exposed circuit board at the top of the cover.

• What I can see in your photos looks very normal. The front wheel throws up a lot of sand and grit, which works it's way into the cover over time. Used compressed air to clean all that trash out before replacing the cover.

• And be very careful replacing the cover. The points wire and the alternator output wires do NOT stay out of trouble by themselves. It is common to crush one or more wires between the cover and engine, which makes things stop working. Cover OFF, bike runs great; cover ON, no signs of intelligent life. 

Hope this helps.

[color=blue]Don't hide 'em, Ride 'em !!
#15150[/color]

ReplyQuote
Posted : 09/19/2020 18:51
Mario Reznik
(@odontologist)
Active Member Expired Membership

Thanks for the heads up on the battery. Fortunately no battery connected so no danger, but will keep it in mind as a priority.

I did manage to hook up an old car battery and with oil in the engine, managed to turn it over. So I know starter works. 

In the meantime, I removed the forks and disassembled them - one at a time - to reveal a lot of gravy and solids on the damper rod and bottom of slider. There was also a very sad looking plastic bushing which disintegrated in my hands, as shown in photo. All the specs are good, including the spring at 567mm, but I'm toying with the idea of upgrading to either progressive springs, or better still, Racetech springs with gold valve emulators. I have put these in my Suzuki SV650s and they are very good. Racetech makes a kit for these bikes. Only dilemma is that the process is irreversible as it requires altering the damper rod. I do think however that they would be a great improvement on the uniform spring and damper rod set up. It also requires some dosh, but I don't mind spending some money on things like brakes, suspension, tyres....you know, the stuff that keeps you upright and on the bike.

ReplyQuote
Topic starter Posted : 09/26/2020 22:32
Richard Whatley
(@wobbly)
Member Moderator

Back to my first post.... don't spend any money until you're able to ride the bike several thousand miles to insure it's a keeper. 

Your front end won't need any more than (at the VERY MOST) a Racetech spring kit. Reason being is that having the axle set in front of the plane of the forks makes these bikes very "slow" in the steering department. So you won't get nearly the response you got on your last bike. In other words, it will be money poorly spent.

But you'll come to love that "neutral" steering which will allow you to take one or both hands off the bars to give you time to do a back and arm stretch while motoring down the road during an 8-10 hour ride across the country.

Hope this helps.

[color=blue]Don't hide 'em, Ride 'em !!
#15150[/color]

ReplyQuote
Posted : 09/28/2020 17:41
Mario Reznik
(@odontologist)
Active Member Expired Membership

I'm  a little confused as to my front wheel. All the specs I've seen quote the R75 as having a 19" front wheel. Mine currently has a 100/90-18 tyre (see photo attached). It looks to be the correct wheel in every other respect.

Does anyone know if they did vary from published specs?

ReplyQuote
Topic starter Posted : 10/06/2020 01:26
Richard Whatley
(@wobbly)
Member Moderator

@odontologist I believe that the R65's came with 18" front wheels. Most of these were "snowflake" mags. 

An 18" wheel would change the geometry and make the bike steer quicker. To get the full R75 "effect" you'll want to hunt up an original 19" wheel. 

[color=blue]Don't hide 'em, Ride 'em !!
#15150[/color]

ReplyQuote
Posted : 10/06/2020 05:02
Richard Whatley
(@wobbly)
Member Moderator

@odontologist I believe that the R65's came with 18" front wheels. Most of these were "snowflake" mags. 

An 18" wheel would change the geometry and make the bike steer quicker. To get the full R75 "effect" you'll want to hunt up an original 19" wheel. You'll also have a better selection of tires with a 19" rim on the bike.

[color=blue]Don't hide 'em, Ride 'em !!
#15150[/color]

ReplyQuote
Posted : 10/06/2020 05:04
Mario Reznik
(@odontologist)
Active Member Expired Membership

Yep! At close to AUD$ 700 (US 500) for a new  used wheel, not sure.

I can get a hold of a rim for about US200 but would like to confirm that hub and spokes are interchangable between 18" and 19".

Then again, as I've never ridden an R75, keeping the 18" set up would give me the R75 "effect" as is. Food for thought.

ReplyQuote
Topic starter Posted : 10/06/2020 16:56
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