Tillitson vs Linkert on XLCH

[ThumpStreet]

Any views on running a Linkert DC-7 on a 69 XLCH as opposed to the stock Tillitson? If it's an acceptable swap,what would be entailed? Manifold change? Will the factory internal throttle still be able to be utilized?Any input appreciated.

[thefrenchowl]

Over the last 35 years of riding iron heads exclusively, I did use all the combos...

The Tillotson is the best if you're a street racer, but fiddly to tune and open to abuse, even by passers by, control knobs way to big and in the open...

Any DC Linkerts are the best all round, easy starting, tuning and mpg... But they are getting expensive these days if you don't have a good stash at home (I have 5...)

The DC requires the smaller pattern cast steel manifold, its 2 screws are not as spaced out as the Tillotson spacer and its successors, Bendix and Keihin.

But a bit of filing can go a long way...

Both carbs are push cable to open, but I always reverse the action and fit a return spring on me bikes.

Patrick

[sportsterpaul]

And I did see a lot of Tillitsons that had caught fire in the bins at the swap meats. And be SURE to plug the vent lines on your tank securely, unlike me, whose 1962 caught fire twice-- because the plug over the vent nipple had disintegrated. Now I have a plug in the pipe up at the gas cap, and another plug down where the vent pipe comes out.

I am running a butterfly Keihin, pre-79, so it has the mixture screw accessible. Nice simple carb, but dang if I can get the intermediate jet fat enough to keep the bike happy off-idle.

[thefrenchowl]

Paul,

Intermediate jet on the Keihin works same as the earlier carbs, it is a mix of 2 things: iddle screw set ever so slightly rich and butterfly ever so slightly open, not resting on its stop...

Try tuning your carb again, ie drop the iddle a touch on the iddle screw and open your butterfly a touch.

You'll soon find the sweet spot where the bike starts dead easy and you loose the hickups/coughs at the transition.

Even by 1979, the Keihin had several versions...

Best one is the oldest one, late 1976, all accessible screws on the outside.

It has 1mm idle jet and 1.80mm main jet. Make also sure you have the rubber blanking plug underneath the iddle jet.

It is not fed from the bottom direct in the bowl, but via the main jet next to it...

Patrick

[EKHKHK56]

Tillotson carbs have the nice feature of being altitude compensating. Probably why so many came on snow machines. Erik K

[ThumpStreet]

Holidays behind us and a couple of other motorcycle projects winding down,I'm getting pumped up to dive into '69 XLCH. I've got to reach out to the community to get some valuable input on a couple of things that have been brought to light.First off some historical education.My XLCH is serial number 69XLCH9771.Does anyone know the date of manufacture of this unit or where I would find this info?Next,along with me correcting my spelling of Tillotson,who is a trusted source of quality parts to restore my HD1C carburetor? I've been doing some research and have found numerous snowmobile applications and some aftermarket pieces but no one so far that has a good stock of wear prone parts for Harley Davidson application.After all,the carb is coming up on 47 years old and was never loved all that much.I was considering change to Linkert DC12 set up but some more research and different owner/mechanic points of view,I have decided on educating myself(with help of course)on the nuances of the Tillotson pumper carb.I do have a decades old memory of when I owned a '65 Triumph Bonneville and a buddy let me take his '68 XLCH for a spin, of that seamless immediate throttle response of the Tillotson.Definitely one of the reasons I had for a "must own" a 60's Sportster.Enough of my rambling for now.Any info on where to find accelerator pump,throttle shaft,quality gaskets,welch plugs will be greatly appreciated.

[thefrenchowl]

Main thing to run a Tillie these days is to have a good supply of fresh and supple diaphragms... Anyone even a touch hard won't work... The rest of the bits is not that wear prone...

You will find dead easy the ones that are just round, without the 2 ears/valves for the accelerator pump... They do work on H-D Tillies as I don't think you will hammer on your throttle like 60s guys did...

If you do, you have to find the 2 ears variety... The Harley race versions of the Tilly for XLRs and iron XRs don't have the pump, so I don't think they are essential on street use...

Cheers,

Patrick

[EKHKHK56]

Great info Patick, thank you. So Jerry R conquered Pike's Peak on a fun ride and reported smooth throttle all the way up on his Sportster with the Tillotson set up. This is where I learned about them being altitude compensating. This is always an issue running Pike's with most carbs because ot the near 11,000 foot difference. Great info from him and Dave C as I recall. I have sourced kits from a snow machine and boat company locally. They had two basic ones but I don't know if they cover the H-D carbs. Perhaps they will. One fellow in Ireland has a Tillotson site but I don't know him. Erik K

[thefrenchowl]

Price a bit stiff, but if it's been all these years hiding from the sun in its enveloppe, it'll be a good'un...





http://www.ebay.co.uk/itm/Harley-Davidson-Shovelhead-Sportster-Tillotson-NOS-Diaphragm-27816-66-98-/231806867537?hash=item35f8c41851:g:30wAAMXQsmFRdVFT

Patrick

[jOe]

another consideration---Tillotsons have to be vented to the fuel tank (typically the fuel tank)