Project bike advice

Have you removed all the packaging from the brand new carb?

Brian

Yes,checked that this morning when I fitted them,made my own cables up so had the slides out etc,the electrics were done by the Ferret,so don't think it's the electrics.
 
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Not so familiar with the Mikunis but my next thought would be, petrol in the float bowls?

Also could you wip a pair of Bing carbs on there and see if runs?

Brian
 
.
Not so familiar with the Mikunis but my next thought would be, petrol in the float bowls?

Also could you wip a pair of Bing carbs on there and see if runs?

Brian
I had a set of Bings on it ,they were showing the same symptoms ,I convinced myself they were to blame,so bought the Mikunis to cure the problem!!!.now it's back to the drawing board.
 
Well I did a compression test,think I found the problem,120psi on right hand pot 15psi on the left.i have turned the engine over by hand in fifth gear,tappets on left pot seem to have clearance,I haven't checked the gap because I started losing feeling in my fingers due to the cold.i'm hoping it's not a holed piston!oddly enough the bike was running when I bought it:nenau
 
Oh dear, let's hope it is an easy fix.
I dropped a valve insert on my R80 in the summer but I was lucky it happened when I was starting it and not when I was riding back home over the Black Mountains.
It just snapped the head of the valve off and subsequent starting attempts drove the valve stem up through the spark plug. :(
 
Well I did a compression test,think I found the problem,120psi on right hand pot 15psi on the left.i have turned the engine over by hand in fifth gear,tappets on left pot seem to have clearance,I haven't checked the gap because I started losing feeling in my fingers due to the cold.i'm hoping it's not a holed piston!oddly enough the bike was running when I bought it:nenau

Well I found the problem,I removed the head on the left hand pot ,did a leak test on the valves by pouring petrol down the inlet and exhaust ports and sure enough petrol leaking through the inlet valve,next step remove the valve and check the seat,I am also thinking of doing the other head as well and give both a good decoke etc and fit new pushrods tubes.
 
levers and master cylinder

Top project looks great ...
might I ask where you got the hand controls from , ie the levers and the master cylinder and what size bore is it , got an R80 on the go and want to get rid of the under tank master cylinder and yours look very smart just the job .
:beerjug:
 
Top project looks great ...
might I ask where you got the hand controls from , ie the levers and the master cylinder and what size bore is it , got an R80 on the go and want to get rid of the under tank master cylinder and yours look very smart just the job .
:beerjug:
I bought them on eBay about 18 months ago,I just did a search for CNC Billet brake and clutch levers,I think I paid about £120.00 for the pair
 
Well I found the problem,I removed the head on the left hand pot ,did a leak test on the valves by pouring petrol down the inlet and exhaust ports and sure enough petrol leaking through the inlet valve,next step remove the valve and check the seat,I am also thinking of doing the other head as well and give both a good decoke etc and fit new pushrods tubes.
Well the seats look ok ,acceptable wear in the guides,I've noticed on the exhaust valve seat two lines which seem to be machined into the straight section of the seat,I think I've read somewhere that this signifies that the head is suitable for unleaded,is this the case??
 

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On a downer

Put my barrels through my parts washer today,I found that the cylinder that had low compression also has a section about an inch diameter of peeled nikasil:(:(,can these barrels be replated or rebored or will I have to replace them.
 
Put my barrels through my parts washer today,I found that the cylinder that had low compression also has a section about an inch diameter of peeled nikasil:(:(,can these barrels be replated or rebored or will I have to replace them.

It's cheaper to buy a decent used set, the 80 barrels are less sought after, though they can be replated, it's probably just as cheap to buy the 100 barrels and Pistons, than replating the old barrels!
 
Try Langcourts or Aptec for cylinder replating and they both do a great job. Has to be cheaper than New or some unknown second hand crap!!
Langcourts i have used many times over the last 20 odd years and they thoroughly inspect the barrells before proceeding..Worth a call.
:thumb2
 
Has to be cheaper than New or some unknown second hand crap!!

Well Fuck you!!

Its a really nice pair of barrels and pistons I've sold John.

Langcourts charge £110 per cylinder and you have to remove the cylinder studs (great fun if you've ever tried it.
 


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