Hi Jim, First off I would throw away the original Nipper Cowlings. Too draggy and very ugly. The Barry Smith cowlings are worth about 7kts increase in speed. The "ears" are perfectly adequate for cooling airflow provided you do a good job of the baffling, the lower cowling is without a gap...

Very interesting posts thanks....I removed similar mounts from G-ARXN (Now G-VICA), but it did not have the case on the back of the engine. Although a very nicely engineered installation it is just too heavy and moves the engine too far forward. 'XN had an extra 10lbs bolted to the tail skid. All th...

Watch out for rearward CofG.....you may find you need it!
Ask me how I know!
Neil

Most likely engine vibration. I get the same on Nipper wing and my RV4
Neil

I have never seen one crack, but would like to see a photo of what has happened. These shrink fit hubs are only good for one or two fittings, as the interference fit is only about 0.002". When you remove the flange it will remove about 0.001" each time. The hub should never be a slide fit ...

I used to use Great Plains, but since the new owner has taken it over their communications have become very sporadic. I would suggest Hummel as a first source. I may be in need of one, so if you do decide to import from the USA let me know, I may be able to share carriage. https://www.hummelengines....

Peter I am sorry, I think we have spoken but I am not sure.
Do you still want the callipers?

Sadly not.
There is a mod that uses the standard 1080 bungee. You will need to modify the “top hat” on the top of the nose strut.
I don’t have any photos to hand or the mod number right now.

Well done Paul. Thank for for supporting us.

These are photos of the nose of the crankshaft that came from G-ARXN which shows what happens when the pinch is insufficient. The flange and shaft have been fretting. The disturbing thing is that the “tinkerer” had had problems removing the flange and had drilled a hole down the side of the crank &a...

I can’t access the photos, but that was probably my first “land away “ after restoring the aircraft. In good company with the B17 which had just received 10,000 litres of avgas….fortunately they had some left in the pipe to fill up the Nipper!

Although it can’t beat a wing tip sight I have done well with fine line masking tape on the canopy.

If you do keep the “normal “ flange use the lightest prop you can find. Hercules are very good. Phots show the nose of a stock crank being crack tested. The owner of this engine has to sign a disclaimer before I will release it. Failure usually occurs either at the key way or the groove for the circ...

It’s the weakest part of the engine. In my mind the “Peacock” shrink fit flange on the nose of a stock VW crankshaft is an accident waiting to happen, especially on an aerobatic aircraft. The nose of the crankshaft was designed to support a pulley driving a fan and dynamo. Where the bolt goes in to ...

I always swung mine from behind the prop and in front of the leading edge. Much safer. Concentrate on what you’re doing and don’t be distracted by other people. The “sucking in” 4 blades after priming and then switching on ignition is just a waste of energy. Prime, set throttle, ignition on. The eng...