harleyKmodel

To ChillyWilly. It'll be approx one to two months before I am back at my shop. I will take photos of the stock untouched M53 bombsight carb throat, if the bombsight venturi is still in place (I can't recall), and of the restored M53 and review my notes to see if it's bombsight has been modified? The same for the MR4 and M53A1 for reference.

So, I am running M53 with bombsite in 55 KHK. We are tuning this week...are stock needles, floats, etc sufficient or what would a recommended change be?

The referenced site for Linkert carbs mentions a Linkert MR5.
The 1965 KRs were the last KRs to use Linkerts and used the MR4A.
When were these carbs used?
On what model?
They also mention that the DC11 is a fictional carburetor.
The DC11 is listed as the carburetor on every XLRTT Factory Race Department Motor Test Card up until the 1966 models and is listed in the Competition Models Parts Supplements.

Mayday53.
The stock Linkert float. Original cork. However no matter what any of the float's type's or materials. Be sure that they are not compromised and in good shape. See H-D shop manuals for float adjustment. It's 3/16" from edge of bowl to top of float.
The high speed needle and low speed needles of the K model M53 are unique to K model Linkert's and need to be correct (some have misguidedly install incorrect needles and have over tighten the low speed). The high speed is steel, and the low is brass. The needle's point needs to be undamaged, if they are damaged, they will need to be replaced. If minor (very minute groves can be fine sandpapered smooth. 600 to 800 grit). Both are adjustable and can be 'adjusted' to suit your engine.
Bore, stroke, cam, valves all need to be taken into consideration and effect the carburetor's jets, venturi, and nozzles If your engine is relatively within stock limits all your Linkert's parts will work. HOWEVER, the carb needs to be overhauled correctly. Most parts and the body itself can be repaired, with the exception of the idle port. If this is damaged or corroded to the point of damage, the body in my opinion is not useable.
THEN, the carb installed CANNOT have any air leaks! This can be pressure tested, and/or if you know what you are doing, you can get the engine running and using a spray can of fluid (your experience choice) spray the manifold nuts, manifold to carb joint, to see if there are any 'leaks'. No matter if your carb is good, you can't tune a engines that has air leaks at the carb and it certainly will never run correctly.

hugoct wrote:The referenced site for Linkert carbs mentions a Linkert MR5.
The 1965 KRs were the last KRs to use Linkerts and used the MR4A.
When were these carbs used?
On what model?
They also mention that the DC11 is a fictional carburetor.
The DC11 is listed as the carburetor on every XLRTT Factory Race Department Motor Test Card up until the 1966 models and is listed in the Competition Models Parts Supplements.

The MR5 is a fantasy carb based on a Big Twin carb and was never used by the factory on anything and Linkert never stamped a carb as such.

Thank you for the clarification.

To Mayday53. I stated 3/16" for the float level, that is for a OH carb. For a SV carb it is 1/4"

To Rubone. I believe you may be correct about the nonexistence of the MR5. I have only seen it listed on Mike's Into The Wilderness Trading, Linkert carb list. However he has never seen one.

The website referenced in the post also has inaccurate info regarding the DC11 carburetors as used on the XLRTT.

I have an NOS M53A1 if anyone needs to see what was in it from the factory.

Hi Robone

Thanks a lot for the picture of your NOS M53A1. Would it be possible to take some pictures of the vent hole on the side of the choke lever or even measure the diameter?


Thanks a lot in advance.

Monti