Can you fit "75" R90S Del'Orto Carbs on a "75" R60/6

[Cat]

Isn't the inlet/intake spigot outside dia. on the cylinder head the same on R90S and R60/6 ?

My type 53 Bing carbs have that fiber sleeve pressed inside that makes the that fit to the intake spigot extra tight and secure. Did the R90S Del' Orto carb also come with a similar inner fiber sleeve for the clamp on installation?

[Duane Ausherman]

That has been done and I don't remember how the person made the adaption fit up.

You do realize that you will lose your simple and very reliable carbs for ones that do work better, but require a lot of fiddling and often.

[Cat]

I've always been happy with those old Type 53's, and its all I'm familiar with, although some think they are steam engine era carbs....and once I've gotten them dialed in, they do manage to work fine for years on end with no other adjustments. I think I've only done two minor rebuilds on them since 1976.

But then, I do like the tuning and I"m not scared to fiddle. I've always admired those Del' Orto carbs of course. I did a lot of searching to see if anyone else has adapted an R90S set for the other /6 series machines but didn't find anything.

What kind of material or alloy would make a good adapter sleeve I wonder?

[Duane Ausherman]

In a few years you will make parts like that on your 3D printer in minutes that fit exactly.

I would look closely at taking the head insert out and making an adapter to weld onto it. I am trying to remember exactly what those parts look like, as I haven't looked at one in many years now, maybe 30.

[Ken in Oklahoma]

I'm nothing like an expert on carbs, but I would be astonished if the "big bore" Del'Orto carbs would work very well replacing the much smaller bore stock R60 carbs. I'm talking about for street use. Presumably a track bike would be tweaked and the carbs would mostly be required to work well within a narrow rpm band of a R60 at speed.

Tuning the Dells would be an interesting challenge.

It's an interesting idea though. Actually more interesting to me than putting fuel injection on an airhead.


Ken

[Major Softie]

It's an interesting idea though. Actually more interesting to me than putting fuel injection on an airhead.
Ken

More interesting, but probably at least as difficult and not nearly as likely to achieve complete success.

[Jean]

I think the Dells would be oversize for the R60...about the same way Bing 40s are a bit oversize for the R100s for casual riding.
Why don't we have Bing 36s?

[Garnet]

I think the Dells would be oversize for the R60...about the same way Bing 40s are a bit oversize for the R100s for casual riding.
Why don't we have Bing 36s?

Mikunis come in all sizes.

[Cat]

Just out of curiosity, those hand operated lever chokes, are they fussier than using a cable choke? I imagine its easier to flood the carb no? Didn't the old Del"orto carbs come with finger operated tickler to prime the carb? The newer ones look like they're all cable operated.

Are there fake Del'Orto units around , like the fake Mikuni's made in China?

[Cat]

In a few years you will make parts like that on your 3D printer in minutes that fit exactly.

I would look closely at taking the head insert out and making an adapter to weld onto it. I am trying to remember exactly what those parts look like, as I haven't looked at one in many years now, maybe 30.

My thought was to find a couple of old 38 mm Del'Orto Carb body's on ebay. Preferably with the finger operated plunger tickler choke, remove the old original "insulator bushing"/sleeve from the bore where it mates to the cylinder head spigot, machine a small adapting sleeve from a proper alloy, and into that adapter press in one of the R60/6 oem fiber bushings like on my type 53's so there is a secure tight fit on that head intake spigot and it would be easily mounted/clamped and removed.

The old Del'Orto carb body rebuilt alone sounds like a fun project.