Author Topic: CR carb issues CR750  (Read 765 times)

Offline adriangsmith

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CR carb issues CR750
« on: May 13, 2017, 03:32:19 PM »
Hi All,
Just finished rebuilding the engine for a friends CR750.
All up together and would not start.
Traced to blocked jets in the carbs.
I removed all the jets and cleaned them out but now have petrol coming out from the overflow holes as marked in the picture below.
Floats valves still shut off manually so not sure if floats have perished or somehow the levels have changed.

So is there anyone who services these carbs in the UK?
Looking for a quick turnaround as he wants to take it to the classic TT in a couple of weeks.

Thanks All
Triumph Thruxton 2004
Honda CB750F1 1976
Honda CB400F   1976 (current project)

Offline philgresty

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Re: CR carb issues CR750
« Reply #1 on: May 13, 2017, 04:49:06 PM »
remove the floats and submerge them in water, if there is a crack in the float, it may be filling with petrol and sinking

Offline royhall

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Re: CR carb issues CR750
« Reply #2 on: May 13, 2017, 05:19:51 PM »
The Classic TT is not until the end of August. Matt Harper at "Harpers ultrasonic" is a carb genius  http://www.harpers-ultrasonic.com/ Ironically he builds the carbs for a number of the teams racing at the Classic TT.
« Last Edit: May 13, 2017, 05:21:51 PM by royhall »
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Offline westfieldandy

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Re: CR carb issues CR750
« Reply #3 on: July 17, 2017, 03:03:30 PM »
I use cr's on all the customer racers,

they are prone to flooding, usually just fine dust in fuel is enough,

always use a clear in line filter, do not rely on the gauze around fuel tap.  make sure float valves are good

make sure floats are good and set correctly,  my guess its just dirt, so many customers bring them to me swearing they've cleaned them out, and the tank, and there is still stuff getting through, the clear in line filter give a visual indication as to whats getting through.

andy
www.good-bits.co.uk


 

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