45" Carb question

[fatass]

Well, since Linkerts are so fricken expensive, has anyone run anything besides a Mikuni 34mm on a 45? I'd like to try a Bendix or SU for the adjustability, but I don't want to be grossly overcarbed.

[M.O.Ther]

I had a 45 servicar that I ran an Amal monoblock on. Seemed to be alright, but my standrds for "alright" might be different now from what they were in 1970. I imagine you could get a 32 mm Amal, mono or concentric, tuned in pretty well on that 45. 'Course good ones of those aren't cheap either.

[lilbill]

i've seen 1 1/4 su's used "back in the day". almost anything would be an improvement, the stock carbs on those were just one step above stuffing a gas soaked rag in the intake.

[Gspot]

Originally Posted by fatass

Well, since Linkerts are so fricken expensive, has anyone run anything besides a Mikuni 34mm on a 45? I'd like to try a Bendix or SU for the adjustability, but I don't want to be grossly overcarbed.

Thi biggest bitch on flatheads is the carb on the left side so starting can be a btich without the proper carb. I would do whatever I could to find a deal on a linkert but I think a small Mikuni would be best. Jets are super easy to find, jets and cables are everywhere, air cleaners can be bought at any dirtbike shop. Plus they're cheap..

[Destralo Roach]

Of course any one who works on MG midgits will be able to help on the SU's jetting and so forth, do the math on a inline four 998cc-1275cc MG midgit motor and you have two carbs for it so one carb with the right jets and needle will work on a 45 two cill flathead.....and cables are no prob and the SU motorcycle aircleener will bolt on....Roach.

[Apehanger Hank]

I have used the following carbs on a 45 motor.
32 mm Mikuni....could probably get by with a 29 or 30 mm, but the 32 was available and cheap.
Honda 450 (DOHC) carb
1 1/4" SU
AMAL - both monobloc and concentric

The absolute best one was the single carb from the Honda 450.
It was a nearly new carb at the time, bet it would take some major work to get one right now.
The Mikuni was a close second and is on the Harley Ableson and will probably be the one I use on my 45 chopper.
Hank

[Trent]

Save your pennies and buy a Linkert!

[47bobber]

Linkerts are where its at. You can go with a Mikuni, but unless you buy it from Harley 45 Restoration it will never run right. They'll start first or second kick with a linkert everytime!

[Creepinogie]

Why would you want to run anything but a Linkert on a 45? The guys that can't make them run either don't know what they are doing or are running a Linkert with a bunch of mixed-matched parts in them. Although I've never heard of running a Honda 450 (keihin CV) carb on them, those are good carbs but the diaphram on those old Honda CV's are usually worn out and pretty expensive to replace.

[fatass]

[quote=Creepinogie;237073]Why would you want to run anything but a Linkert on a 45? quote]
Ridiculous prices. Same reason I don't own a '32 Ford or a Knuckle.

[Creepinogie]

32 fords and knuckles aren't that spendy if your willing to do a little work. same with Linkerts. I don't recall Mikuni's being real cheap either. But as long as it runs I guess. I'm just fundimentally opposed to putting a Mikuni on a vintage machine when there's nothing wrong with the origianl carb. I think there is a Mikuni for a 45 on the bay right now. But same with a 45 Linkert....

[Gspot]

[quote=fatass;237077]

Originally Posted by Creepinogie

Why would you want to run anything but a Linkert on a 45? quote]
Ridiculous prices. Same reason I don't own a '32 Ford or a Knuckle.

Linkerts for 45's are pretty abundant and aren't really expensive. Maybe you'll pay a lot for a 74b or bigtwin one but the 45" ones are pretty abundant. I may have a nice one I'd sell. I think it's a M25??? can't exactly remember. I'll check next week if you're interested as I plan on running a bombsight linkert on my 45 I'm building

[45.]

built this sled in the early 80's http://1whoof.us/images/Bike%20shots/45_bike.jpg, carb I built it with
was an 1 1/4" Linkert M-51L, I ran the bike with: an
M-51Linkert, a Toiletson, an SU from a 50's era MGA
sportscar, and a Bendix from a sportster. WARNING: Running
a Tillotsin carburetor on a flathead can result in a fire!
If you run an SU make sure the aircleaner has a good seal to
the carb, doesn't take much dust to seize the slide in the
bore. The Bendix is on it in the above photo taken in
the early 90's.

[FRANXNBEENZ]

Tedds V-Twin offers a complete Sudco Mikuni kit for a 45. It even comes with the twist grip and cable.

[Sporticus]

Linkert DC10. Couldn't tell you what it originally came from. Certain vintage Servicars came stock with some version of the DC Linkert. This is attached to a Servicar intake (bolt pattern matches). The ID of the carb and the ID of the intake manifold didn't match, so I made the aluminum spacer with a conical (right word?) ID to blend the two inside diameters smoothly. The DC Linkerts have their choke plates in the stock air cleaner. Without the air cleaner, you have no choke. That's why there's another float bowl in the photo with an Amal tickler attached - so I can start the bike without choking it. I've seen this done before. I have no idea how well this setup will work - I'll get back to you. I need to run a support from the carb to the motor mount. The carb is heavy and hangs off some distance.

I got this carb cheaper than an older Linkert would cost. Plus, I think the DCs are very cool looking.

[Dragon]

Good stuff Scott, this thread needed more tech. Does that bowl extender say Webco on it ? There was one on a DC I sold awhile back...

That tickler idea is about brilliant, too.

[Gspot]

Originally Posted by Sporticus

Linkert DC10. Couldn't tell you what it originally came from. Certain vintage Servicars came stock with some version of the DC Linkert. This is attached to a Servicar intake (bolt pattern matches). The ID of the carb and the ID of the intake manifold didn't match, so I made the aluminum spacer with a conical (right word?) ID to blend the two inside diameters smoothly. The DC Linkerts have their choke plates in the stock air cleaner. Without the air cleaner, you have no choke. That's why there's another float bowl in the photo with an Amal tickler attached - so I can start the bike without choking it. I've seen this done before. I have no idea how well this setup will work - I'll get back to you. I need to run a support from the carb to the motor mount. The carb is heavy and hangs off some distance.

I got this carb cheaper than an older Linkert would cost. Plus, I think the DCs are very cool looking.

I believe the DC cam on the early sportster..57-64???? and maybe later K models not sure on the years. Never seen one on any of the servicars I've seen. They are cool though

[Sporticus]

Thanks! Yep, that's a Webco piece. I wish I could take credit for the tickler, but it was the work of someone else a long time ago. It is a very straightforward installation, though. I could do it now that I've seen how someone else did it.

There was a bike with dual DC Linkerts on here(?) a while ago that also had Amal ticklers on it, so it must have been done by other people who didn't want to use the stock aircleaner/choke setup.

Gspot - I have an early Sportster factory manual that covers all the carbs used used on early Sportsters. It lists the Bendix, DC Linkert, and even the earlier Linkert (model unknown). I've never seen an early Linkert on a Sportster. Maybe on K models? Anyway, literature on the DCs isn't common, and I'm glad to have found a lot of info in this service manual I had gathering dust under my grinder.

Originally Posted by Dragon

Good stuff Scott, this thread needed more tech. Does that bowl extender say Webco on it ? There was one on a DC I sold awhile back...

That tickler idea is about brilliant, too.

[Sporticus]

More on DC Linkerts.

Let me steer this thread off topic for a moment. French Owl posts here, I believe. I hope he won't mind me posting some info on the amazing twin DC Linkert setup on his KHK Special. Here are the specs from his website, followed by photos. I don't know how he chokes the carbs.
http://www.harleykrxlrtt.com/khk%20specs.htm


Twin carburettor set up: uses two Sportster 1957 to 1965 Linkert L&L carburettors. The rear main alloy body is as it should be while the front one is reversed to get symmetry and narrow manifold. Both venturis re-machined to H-D XLRTT race specs (38mm), bigger 40mm butterfly throttles from 1966 Tillotson carburettors. New idle chamber screws with intermediate slot to cope with the bigger butterflies. Special twin throttles lever. Special alloy air filter back plate with sliding plate choke assembly. Air filter cover from industrial roof extraction fan. Special manifold made with a set of 4 special nipples, flanges cut off from early Sportster manifolds and various cuts of 1”¾ exhaust pipes with the “right” bends. Special bracket/ clamp to hold in position with O rings and narrowed standard Sportster screw clamps.

[fatass]

WOW, that's nuts! I'm thinking that's more than a stock K-model engine.

I'm going to ponder my possibilities here, as I've got an old Bendix and access to a couple of SUs. I'm just finding it hard to justify $300 to $400 on a carb for an engine I paid $800 for. I'll look out for a DC-10..that's pretty cool. Missed an M18 on Ebay for $150, but this is a small venturi carb.

Creepinogie, lemme know where I can find the affordable Knuckle and '32. Last swap I went to had just a set of broken (repairable) Knuckle heads for $2k. I guess it depends on you affordability range.

[itusedtobeaboutchoppers]

Originally Posted by fatass

Last swap I went to had just a set of broken (repairable) Knuckle heads for $2k. I guess it depends on you affordability range.

I'm getting an FHP knuckle engine together now; and its def. the most expensive for parts that I've had. Quality of parts is iffy at best; (V-Twin shit, not FHP) and Taiwan Ted seems to have the only game in town for alot of it. This is just personal exp. now... but I know a few others w/FHP engines, and it took quite a bit of tweaking/fitting to get them to be reliable, run OK, and not leak like a sieve. I believe (if memory serves me correctly) that a knuckle from say Accurate, starts @ around 10K; and that was a bone stocker.. (ugh!) Then again, there was a post here a few days ago about a complete orig. knuck on CL for like 6K... to me it seems like a steal.. ?

[Creepinogie]

I just passed up a running knuck for 7500. Not original frame or front end. But they can be had. Trying to build them from a set of cases is not the way to go if you want to save money. And in ND 32 fords are laying all over the place. You just need to work on them.

[45.]

[quote=fatass;237482]Missed an M18 on Ebay for $150, but this is a small venturi carb.

The M18 is a 1" throat, fixed high speed, no adjustable high speed needle, this does not matter in the city, it does on the highway. If you have a good Bendix I would suggest making an adapter for it to the 45 manifold, measure the throat of the intake manifold, 1 1/4" is the one you want.

[47bobber]

Spending $200-$300 on a Linkert is money well spent. In the long run it will save you a ton of aggrevation.

[fatass]

What is the interchangability between M18s and M88s?

[sLowrider]

I run a 32mm Amal MK1 on mine. I get 65mpg compared to my mate who gets about 35-40 with a Linkert. My motor's tuned a bit but baseline settings should be:

#20 pilot jet.
106 needle jet
#3 slide
240 main jet.

They're cheap and replacement parts aren't expensive - the only down side is they can fill up with rainwater but they're easy to drain and a squirt of WD40 usually sorts them out.

Cheers Johnny