How to remove limiters in carbs....

All about the BT1100

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Registriert: Sonntag 8. Mai 2016, 08:59
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How to remove limiters in carbs....

Beitrag von Doc44 » Sonntag 23. Oktober 2016, 17:50

How do you do it? Any advice? With pictures would be great.

Also, anyone have a spare BT manual in english they want to sell?


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Re: How to remove limiters in carbs....

Beitrag von WullDee » Sonntag 23. Oktober 2016, 20:39

don't know how to remove the limiters, but here you are the workshop manual.

Die linke Hand zum Gruß,


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Big Ade
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Re: How to remove limiters in carbs....

Beitrag von Big Ade » Montag 24. Oktober 2016, 16:52


The Mikuni carbs are a similar design to the old Stromberg (constant depression) carbs that were fitted to cars. That is they have a piston that rises inside a dashpot to open the venturi, be warned - the pistons have a rubber membrane that is easily damaged. The plastic limiters sit inside the dashpot over the piston to stop the piston from opening fully so the engine is starved of fuel at 6,000rpm. If you remove the limiter you will allow the piston to raise up to its limit and the engine will suck in all the air/fuel it can take. BUT, the main jet is now too small for the extra air flow so your mixture will be lean and could cause overheating and even melt your piston crown! So you need the Allen kit that includes new jets for your carbs and a full flow air filter.

The plastic limiters are removed buy removing the top of each carb, taking out the plastic bung and then replacing the tops. The dashpot top fasteners are notoriously tight so loosen with WD40 and a smart tap to shock the threads free. You need to take off the fuel tank, air box, etc.

BT1100 is available on a CD there is one here for sale now "Home > Buy on eBid > Cars & Vehicles > Motorcycle Parts & Accessories > Manuals & Literature > 132424181"

Once you have your dog sucking well you need to let it breath out well too, get some open/full flow cans.




Surrey Guy
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Re: How to remove limiters in carbs....

Beitrag von Surrey Guy » Samstag 18. Mai 2019, 07:25

Good advice Ade,
I have just been reading your thread and you have answered some the questions I was yet to ask.
I removed the AIS valve today hoping to help the smooth out some of the back-fire, wasn't a difficult job to do, except I can't find a suitable plug to block the head outlets, so for now I have linked the pipes together behind the side panel, but I would like to remove them to tidy the engine up a little.
My next job will to be fit the TOPHAM conversion once I get one & take out the limiter.