Gilera Bi4 Nordwest 3d scanning/modelling

[Duranti]

Hello lucakilm,

Thank you for your kind comment, I appreciate it! 

Regarding the intake manifolds; it would certainly be possible to replicate them. And the process I would do to reverse engineer them would be the following;

1. 3D scan the manifold in it's complete state, including the rubber.
2. Strip the rubber from the aluminium "frame", and 3D scan again.
3. Figure out which material (aluminium and rubber) and hardness of rubber (using a shore durometer).
4. Model the aluminium and rubber parts, which should be quite simple.

Then comes the hard part, which is figuring out the most cost effective manufacturing method, and how many pieces are going to be produced, a factor which is usually the "make or break" factor with regards to cost, as usual; more pieces equals lower cost.

There are alternatives though, for example producing 3D printed models of the aluminium frame to enable investment casting of the "frame" in small series'.
Also, it would be possible to investment cast (or machine from billet) the die for the vulcanization process, which would require a die that can handle both the pressure and heat.

Either way it would require a certain amount of effort and financing to produce a replica of the original intake manifold.

Another alternative would be to completely redesign the intake manifold to allow for the rubber part to be mounted to both the aluminium "frame" as well as the carburators.
This would (given that there is enough space for a solution like that) be the simplest and most cost effective solution, because you could machine the aluminium "frame" from a relatively thin piece of aluminium, and you would not need to vulcanize the rubber to the frame, which would eliminate the costly pressure casting die!
Also, for the simple rubber part it would be very easy to machine a split die for pressure casting.

I think that to summarize this information; the best thing, in my opinion, would be to re-engineer the manifold (due to reasons of cost of manufacturing to the original specification), if possible.


Sorry for the long message, I hope some of this information is of use!

Please, if someone else can supplement (or disagree completely, haha) this information, please feel free to comment! 

[Duranti]

Found someone who's already done it 

Should be a simple thing to design and manufacture.

[lucakilm]

Hey Duranti thanks a lot for your prompt and extensive response! Can really see that you're a pro!

I also think that the last alternative it's the best option, I was going to do the same when I rebuild my engine to new condition...well not me but my mechanic...The thing is that I don't know if it's important to reproduce the exact angle of the aluminium part, which would involve to make a scan anyway of the part, and than the new hose needs to be designed.

I suppose that the aluminium part, after having made a design could be easily reproduced here in Italy or elsewhere  and that we could ask to the external company I mentioned to build the rubber part making these a two steps process.

Of course this will all depend if other people in the forum are interested to lower the final price.

Thanks a lot for your contribution and to waste your time with me.   

[lucakilm]

I forgot to mention how interesting that last picture you posted is! seems like an injection carburetor like the Lectron ones.

where did you get it from? impressive how many pictures you manage to find

[Duranti]

Hi lucakilm,

It's my pleasure to respond to your post, no waste of time!

I am actually searching for the original manifold on ebay (I have only ever seen one Gilera 600 for sale in Norway, parts are not available here at all), because I am going to include it in my model, but they are difficult to find! 

Honestly I was not aware of the angle of the manifold, I will make an accurate model of this part (for the NW) when I find one, and share my findings! I'm also planning on trying to find an RC600 head and intake manifolds in the near future, and when I do I will 3D scan them, for another project related to my current 3D engine project, I'll let you know my results of the 3D scan when it happens.

I totally agree that with a proper design it should be no problem to produce both the aluminium, and rubber, parts in Italy (perhaps the best country in the world to produce motorcycle parts!), or elsewhere.
The price will definitely be reflected by the amount produced. Also many companies are not interested in spending their time programming tool paths and jigging for one offs or small series production, at least that is the mentality in Norway, I guess many other European companies are more "friendly" towards enthusiasts like us. 

Regarding the picture; I was just lucky to stumble across it on Flickr, there is a user called Martin Burrow who must be a big Nordwest fan! I believe the carburetors he's mounted are Dellorto PHFs with accelerator pumps! I an uncertain of the sizes though.

Living in Norway I have always been starved for motorcycle information, so for many years I've spent much time and money collecting all kinds of information through the internet regarding my favorite brand Gilera, and especially the Rally bikes, and also the RC750R engined Bimota GB1.
I find it satifying to share pictures and information with fellow Gilera fans. 

[lucakilm]

I'll see what can I do for the intakes ok? If I find a pair I can send them to you ok? Ciao

[Duranti]

PM sent my friend 

[fanelliale]

Hello guys. If your initiative can help our community, I can help you find a collector to sacrifice.

[federosso]

io devo chiedere scusa per la mia poca "internazionalità".

Non mastico bene l'inglese e devo usare un traduttore automatico per i post di Duranti.
ne intuisco l'interesse e la passione. Senz'altro la competenza.
Alle volte però mi collego dal telefono e fare le traduzioni diventa difficile. Allora mi perdo i post e poi resto molto indietro.

Dunque, ho capito male o cercate i collettori '89 da "sacrificare"?

Se si ne ho io disponibili.
avevo iniziato un lavoro di riproduzione casalingo mai portato a termine, ne parlavamo qua. http://www.gilera-bi4.it/public/forum/index.php/topic,15642.0.html

esempio:

[attach=1]
[attach=2]

Se serve cerco i pezzi in garage.
Mi furono donati dall'ing. ( RC_true) come sciupabili allo scopo... essendomi io arenato sarò ben contento di destinarli a chi ne saprà fare un uso avanzato.

Sempre che abbia compreso di cosa parliamo.

[fanelliale]

Da quello che ho capito si parlava del collettore "doppio' (tipo nordwest per capirci).
Ma credo che nel principio poco cambi....

[federosso]

non dovrebbe cambiare dal lato carburatori ma dal lato testa sono completamente diversi. Come senz'altro sai.
Non credo che in quel caso i monconi che ho io possano tornare utili.

Però... il collettore doppio se non ricordo male è già stato duplicato. Immagino che un 3D o un cad ci sia già.

Dovreste provare dai cugini del g4t. Sempre che esista e che lo vogliano condividere.

Ero contento per i collettori singoli '89, quelli sono realmente "introvabili".
Ovvio che si sopperisce in vari modi alla mancanza, ma se uno lo volesse uguale all'originale avrebbe serie difficoltà di trovarlo in condizioni buone o pari al nuovo.

Boh, se servono i monconi che ho io li ricerco in garage. Mi pare di non averli dati via con la moto...

[Duranti]

@federosso & @fanelliale,
I'm sorry for my absence during todays conversations.

Thank you federosso for the interesting pictures of the split manifold, and also for the link to the other thread (http://www.gilera-bi4.it/public/forum/index.php/topic,15642.0.html).
The problem with the manifold(s) is obviously a big one; out of production, and when you finally find them (new or used) the rubber might be suffering from age deterioration.
Thankfully there are many skilled people here on the forum that are dedicating time and effort in finding a permanent solution!

From an engineering standpoint it should definitely be possible to find a satisfactory solution that could be produced in series (from a 3D model/engineering drawing), but I am not sure that I can contribute more, to solve this problem, than the wonderful people of this forum that are already involved in finding the best solution. 

The intake manifold I am going to use for my project will be a completely different one from the various original Bi4 intake manifolds, but when I find a Nordwest intake manifold, I will happily scan/model/design a possible solution that can be produced in series for the forum.
The RC600, as you have already pointed out federosso, is a different design than the Nordwest, but it could share most of the same engineering principles with regards to designing an alternative solution to the original parts.

I appreciate your enthusiasm and comments, thank you guys!

[Duranti]

A little side project while I'm waiting for parts to arrive in the post 
These calipers (Sx & Dx) will also be part of the project I'm doing, that I will reveal in due time, but for now I'm just digitizing parts to go into the main model.

I love Brembo CNC parts, so nice! 

[Matte]

Ollallà, splendid work, it seems to be a photo, not a "drawing"

[Duranti]

Thank you Matte, much appreciated!
I wanted to do a proper measuring/modelling and rendering job to justify the beauty of this classic racing caliper!

Also, I need an accurate caliper geometry to design the caliper mounting brackets, which I will eventually get cnc machined (when I can afford it). 

PS: I see now that there are some cut-outs missing on the caliper!  Back to work for me, update soon!