Alloy welding + preventing weakness/cracks advice needed

[generatorshovel]

I'm about to tackle raking an alloy Honda frame & have no idea what grade alloy is used, only that the neck area is cast, and the frame rails are extrusions.
After searching the 'net, and this forum (ALWAYS a wealth of information & experience to draw from) I'm thinking of using 5083 plate & 5183,4356, or 5556 filler rod (I will not be the welder, but need to have some idea of the best choice of alloy & filler to buy)
Will the frame need to be stress relieved when finished ?
Tiny

[rouse]

The most common filler rod all around would be ER-4043.

I have seen some strange thing happen with Japan aluminum, so do some test welds if you have parts that are being cut off, if at all possible.

Stainless steel wire brush to clean just before welding, wire wheel on grinder even better.

Rouse

[WOODY@DDLLC]

Don't use the brush for anything else!  Reserve it just for aluminium! 

[Peter Jack]

You'll be dealing with anodizing. Be sure to get rid of it before you weld to lessen the chance of contamination.

I like Rouse's choice of filler rod. 4043 tends to be malleable and is pretty compatible with most alloys. Remember, the weld is to hold everything in position and the design is what should make the structure effective. The Japanese seem to have messed with the composition of both their magnesiums and aluminums resulting in more difficult to weld materials.

Keep a careful eye on any area that you modify and you shouldn't run into any difficulties.

Pete

[kiwi belly tank]

This is a critical structure that would hurt you big time if it failed. If you have any doubt in your welding ability, tack it up & take to to a welder. Have a chat to some bike guy's that have done this mod on aluminium frames & are still around to talk about it.
  Sid.

[maj]

Tiny do you have a handling problem your trying to sort out ?

I had a raked frame on the busa and changed back to a standard frame after a couple of yrs
It was done by Bob Martin engineering , frame sliced near the head stock from below and a machined wedge fitted then welded
i later welded a 5mm plate on the bottom as extra security when i was adding a lot more weight

what made me change back was after Bubs 2010 , the track was quite damp and all the fast bikes like the busas were having handling problems , except our 750
it was very stable and ended up fast bike of the meet with a 229mph pass
750 in standard form i thought had the steepest rake of any of the bikes that should have been going over 200

so my thoughts are if it aint broke dont fix it  

[generatorshovel]

Tiny do you have a handling problem your trying to sort out ?

No Greg, but I have a HUGE problem changing plugs, I loose a few layers of skin trying to fit my hands in impossibly small areas,and as the plugs can't be shifted, I decided to move everything.
37 degrees has been my favored rake for a long while, the HD has it, the V8 bike had it, as did Cec Frasers 175, now the 250, all handled very well.

Kiwi belly tank,Peter Jack,Woody, Rouse, thanks for the wisdom,,I can't weld for shyte, I have a good mate 5 hrs away, Kiwi Trevor, welds alloy very very well, he will be my preferred welder.

To get my butt lower I need to make a longer swing arm too, but steel will do for that.
Thanks all
Tiny

[rouse]

Don't use the brush for anything else!  Reserve it just for aluminium! 

That is sound advise, Never use anything other than stainless steel wire bushes on any none carbon steel materials, and never use the same brush on different materials.

We mark a used wire bushes or wheels, with the material it was used on just to prevent cross contamination between materials.

That's a practice will save you a lot of "headaches".

BTW I was not counting on you doing any anodizing, If not, OK, if so, that could be a hole new can of worms in order to get color matching.

Rouse

[generatorshovel]

No anodizing Rouse (1st pic was taken at night, and the frame looks kinda anodized, but it's not, but the japs tend to coat their alloy with a clear coating that takes a bit of elbow grease to remove)
Tiny