AIRHEAD DARK SECRETS & TIPS - AFTERMARKET PARTS & SUPPLIERS

Books and workshop manuals



Battery

Replaceing Airhead Battery
Manual suggest 28-30ah battery.
Stick with this. These bikes electrical systems are fairly
primitive and similar to an old cars systems.
Smaller battery WILL cause alternator issues / replacement in the near future

Check outTOYO brand batteries from www.beiterbattery.com
the skinny /5 style battery is a perfect fit on the BMWs. 12v20p


Brakes

Fluid pressure switch
The AFT brake system uses a brake line splitter under the tank.
One brake hose to left AFT caliper.
One brake hose to the right AFT caliper.
The splitter also houses a fluid pressure switch which operates the back brake light.
If this is faulty go to Midas, take your sample along and you will get a replacement -
(Hilman vogue pressure switch -not guaranteed).
However, with the sample you can easily get a match.


Cables


The Cable Clinic  021 9399358
Parow Bus Prk,
Jean Simonis Av
Parow (Western Cape)


Cafe racer bits



Carburettors

Bing carb diaphragms :
Local Alternative: Diesel Electric Parow or other Bosch dealers.
Ask for 40mm bing/ strohmberg cv carb diaphragms. Exact replicas of BMW bing 40mm ones.
Total cost of R17 each (At time of writing) works 110%.
Revs not coming down immediately when you pull in clutch /Do you have to labour the motor to pull down the revs?
Then you need new diaphragms!


Clutch and actuation



Electrics


ICI Unit Replacement
Replacement part ICI Unit M1/M2  (Supplier: Goldwagen)

Ignition
Ignition Trigger/ Hall effect Sensor
On any airhead with transistorised ignition your friendly BMW agent will tell you that the trigger mechanism concealed inside the timing unit is a non user serviceable part.
Cost of replacement in 2002 was R 3800.
That price has probably gone up to R 13.8K by now.

Cause:
Unsupressed sparkplug caps, the boxer does not like.

Solution:
The unit can be dismantled and the trigger mechanism replaced
with a VW item which is identical in form and function in every way at 1/10th of the cost.
Think it was from a Passat or Golf of the same vintage approx. 1983.  
A bit of soldering and swopping of original circular cup with 2 cutouts (Twin BMW boxer) against the one supplied with part 4 cutouts (inline 4 cylinder) and you are back in business giving a salutory finger to the friendly BMW parts dealer.
Mission accomplished for R 350. (At time of writing)

Oil pickup sensor:
The thread is much more course than "typical" sensor unit threads.
Master parts Bellville
Comes from BMW chain driven car ( think he said M10)
Part number 04428
"febi oil pressure switch"
R 45 ex vat. ( At time of writing)

Ignition Coil
Possible replacement: Harley coil part # 31614-83A
Not sure which date ranges on your airhead.
Picture is here:
https://smg.photobucket.com/albums/v1...harleycoil.jpg

Airhead charging / voltage regulator / charge light

Airheads ( mine is old 70's with "points") start to develop a charging issue.
Charge light will go on and off all the time.
Most likely the voltage regulator.
Worth replacing anyway at age!

Diesel Electric
Parow
PART NUMBER 0192062007  
R96 excl (At time of writing)

The original type is mechanical ( I understand it works like a relay ) and they get sticky with contact breakers. New type is electrically actuated.Sits on right side just below tank badge.
Square black box. Simply unplug, remove, replace, plug in, go ride.

Starter motor alternative: Nippondenso  https://www.motoelekt.com/ignition.htm

Starter Relay : Tip
Problem:Melting Red wire (The one running from headlight in main loom to under tank into starter relay)
             Due to wires touching when headlamp is pushed back in / Wires touching short circuiting

Solution:Cut the thick red wire on left hand side of bike running from the starter relay.
             Add a 30Amp in line fuse.

Beancan repair
https://www.distreman.co.za/

Engines

Rotor Puller
Option 1
A cheap rotor puller can be made with some m8 threaded rod.
Grind some +_ 4cm of the thread away and round the tip, bend the rod  +_ 12cm to make a handle.
Remember to have a nut on the remaining thread
to repair the thread where it screws into the rotor.

Option 2
Cut off an old allen key which you insert into the rotor and then use a  bolt to pull the rotor.
The bolt will also need the end ground away so you dont damage the rotor thread on the way out.
It can also be made from hardened steel M8 bolt, about 100mm long.
Ground off 50mm of the thread.
Using hardened steel means that you don't need to repair threads.

Oil filter canister depth.
Here are some notes:
Oil canister depth and use of shim and/or paper gasket.
O ring nominal thickness is 4.0mm
Target groove depth should be 3.3mm for correct O ring compression.
My canister depth measures 3.5mm
Shim measures 0.3mm
Fitting order; Filter, shim on canister lip, O ring, cover. Note no paper gasket.

All you need to know about it is here
https://www.largiader.com/tech/filters/canister.html

Exhaust


Removing exhaust / engine nuts ( the ones with fins on it)
Do not hit the fins with a hammer.
They will bend and break! Spray thm with Q20 generously , leave for a day,
then turn off ( unscrew) with a very big water pump pliers.
NB - Always apply anti seize compound when reassembling.

NB Copper slip will cause exhaust nuts to seize -
Product BMW "assembly paste"
Castrol Optimol TX - BMW part number 18219062599.
Other Options: Spanjaard Nickel anti-seize compound. (Most Hardware & Motor Spares retailers)


                                           

Alternative
Take the bike for a short ride to heat the exhaust nuts.
This will make them come of easily.
If not, don't force them and rather get the hacksaw to cut them of.
The exhaust nuts are cheaper than fixing the treads on the cylinder head.


Fairings and screens

Supplier of custom screens/bending:
Acryl Trading
5 Kouga str Kaymor Ind. Stikland
Bellville
Cape town
Tel 021 9171498 or  082 555 4422

Fairings:
Forum member : Freak ( Aka Freek de Villiers - contact via FD Worx )



Forks and shocks

Upgrades Fronts

Gold vavle emulators -  www.racetech.com
Telefix Fork braces -  www.spec2.com  
Fork Brace Local Supplier:   Forum member : Dustdevil (Altus Pienaar)
Stiffer Linear Springs -  wilberssuspension.co.uk  

Rear

https://www.mpcustomvalve.co.za  (Cape Town)
Martin Peatzold 021 551 8844 /
Forum Member - Superfoxi (Mike -Cape Town)

Frames and fittings

Dismantling Swingarm from Mainframe:
No special tool needed. Buy a standard 27mm socket
and either grind it's outer diameter slightly smaller,
or get someone to machine it down.
There is no shaft that runs straight through,...
Once nuts are removed, undo the threaded bits with an Allen key.

Recommended Sandblasters & Powder Coaters:
A&A Powder coaters - Speak to Bill
4 Romn Park
Kyalami Road
Killarney Gardens
Tel: 021 557 1086

Schipper Steel - Speak to Willem
Phone: 021 511 0280
Fax: 021 511 0256
Physical Address:
Cnr. Lowestoft St & 2 Leopard St, Paarden Eiland, Cape Town, 7405

Millroy Artisands
5 Berbax Park, 41 Berkley Road
Maitland, Cape Town
Western Cape
South Africa
Phone: 021 510 0911
Cell: 083 310 1428 (Keith)
Cell: 083 700 1017 (Miguel)
Email: [email protected]

Gearboxes



Handlebars and controls



Instruments

Speedometer & Tacho Repairs:
DJ Instrumenst
680 23rd Lane
Rietfontein
Pretoria
0067
Contact : Dolf Niejs : 0836293448

Terry (Wirespokes) Vrla
776 SE 3rd Ave
Hillsboro, Oregon 97123
USA guru - highly recommended on ADVriders!
He also repairs sheared cable housings - like the G/S !

Lighting

HPN Fairing/ Light
When fitting and HPN front fairing the original headlight was replaced with a larger
diameter light of a K100.
As cheaper and more readily available alternative is a VW Golf hadlight (Diameter 195mm) forund
at most Auto Spares outlet.
R300 ( At time of writing)

Luggage



Mirrors and fittings



Mudguards and fittings

Side Panel Rubber Grommits

Rubber Products & Mouldings
5th Avenue and Voortrekker Road
Maitland
Cape Town
Tel: (021) 593 2110

Tygerberg Rubber
Binder St
Parow
7501
Cape Town

021 9398107

Seats and fittings



Service items

AIRFILTER ON PRE 1981 MODELS
Older airheads from approx. 1978 vintage with aluminium cast airfilter housing
The part number is the same as for a standard Ford Escort dogbone.
Simply take old filter and look up in the GUD or Fram manual to source equivalent part at a fair price.



Stainless steel accessories




Steering

Head bearings from BMG 320-28 for the top and bottom

Stickers, badges and emblems

Original Badge Replacements:
Original 70MM BMW tank badge part 46637686746
that fits the R80 G/S and others @ $12
go to the BMW car dealer and buy
BMW car part 36136758569 which is more attractive and cheaper @ $8.



Tanks and fittings



Tools

C-Spanners local Supplier  (Standard and travel version)
Forum member- Zebra    www.flyingbrick.co.za



Transmission



Tyres



Wheels


Websites & Links to all Airhead Matters PARTS - OEM and pattern:

https://www.theboltguy.com/R45.htm
https://www.advrider.com/forums/showthread.php?t=546963
https://www.motorworks.co.uk/vlive/Shop/Parts.php?T=3&NU=15&M=20&Ct=FA
https://www.motobins.co.uk/
https://www.gs-airheads.be/
https://www.advrider.com/forums/showthread.php?t=564062
https://www.beemershop.com/
https://www.motoelekt.com/ignition.htm
https://www.euromotoelectrics.com/product-p/boigncoil-r426.htm
https://www.ibmwr.org/otech/partsubs.shtml#Airheadoilfilter2
https://www.moorespeed.co.uk/
https://advrider.com/forums/forumdisplay.php?f=85
https://www.wuedo.de/klassik/index_r75_7_uk.html
https://www.ukgser.com/home/
https://www.siebenrock.com/en/products/technic/
https://www.motoren-israel.com/index.php?cat=c28_Engine.html
https://www.maxbmwmotorcycles.com/fiche/fiche.aspx
https://www.boxxerparts.de/
https://www.benchmarkworks.com/onlinestore/partno.htm
https://www.bmwbayer.de/index.php?page=categorie&cat=316&sibling_id=317
https://www.flatracer.com/#
https://www.meyer-bikes.com/ersatz3.php
https://www.ulismotorradladen.de/uli/Web/shop/Homepage.aspx

Add-ons

https://www.boxercafe.com/default.htm
https://www.euromotoelectrics.com/
https://www.bmwboxersupplies.com
https://swt-sports.de/sess/utn;jsessionid=154c717728ab706/shopdata/index.shopscript

Modifications
https://www.q-tech.de/

How to / DIY
https://jhau.maliwi.de/mot/r-elec.html Motor Spares retailers)