Turbo charging my B12

[majortom4]

Goodbye fuel gauge. Hello boost and fuel pressure gauges

[Phill106]

The pipe you can leave to atmosphere or just put a little filter on it, or a filter to the casing. It's only case ventilation for any vapour 

[majortom4]

The pipe you can leave to atmosphere or just put a little filter on it, or a filter to the casing. It's only case ventilation for any vapour 

Thanks for that. Know anything about the wiring???

[Paulm]

Wire the scavenge pump up separately to a switch with a permanent live so you can leave the scavenge pump running for a few seconds after you shut off the engine so there is no oil left at the turbo,no smoke at startup then.

[majortom4]

Ok will do. Thanks for that will get that wired in tomorrow or Tuesday, hoping my pump is going to be adequate for the oil return as it has to feed it up...... I'll find out when it's all wired in I suppose....

[majortom4]

just wondering, whats a good insurance company to go with for a turboed bike?? just wondering if there is a special one with cheap prices that people use???

[Paulm]

Mines insured with bikesure,they know all the mods £216 fully comp this year

[majortom4]

Mines insured with bikesure,they know all the mods £216 fully comp this year

Thanks Paulm I'll give them a shout at renewal time.

[clivegto]

Mines insured with bikesure,they know all the mods £216 fully comp this year

I am with them as well.

[majortom4]

Been having a right nightmare trying to mount the fuel pump and pressure regulator without it looking stupid. Finally just about found a place with a couple of cable ties and they are on. Also plumbed in my manual boost controller to the in-built waste gate and blow off valve. Isn't looking as sharp as I wanted with the pipes but can't do anything different.

drilled tank overflow and blocked off hole at top so now have a fuel return. Fitted air filter to turbo, wired in fuel pump to switch live.

not too much left now really. Just waiting for some piping to come for the tubes to the plenum. Then it's just welding downpipes (probably going to be a lot harder than I imagine) , fitting AFR gauge and getting oil return plumbed in when the parts get here. 

[majortom4]

Then have the fun part of trying to set her up right. Definitely going to need you guys help on that bit!! :)

[majortom4]

Just a thought. Before I put my carbs back on, is there anything that I need to do to them?? Plug any holes or change anything??? (Apart from jetting if needs be)?

[majortom4]

Ok so about to tackle pitot tube size, 

just wondering if this concept would theoretically work?? (Seems good to me)

so what I read was that instead of just drilling a hole in the pitot tube, was to drill and tap a hole the correct size to fit a main jet in. Then if the bike runs lean or rich you can change the jet size in the pitot tube rather than re-jetting the carbs. Now I was looking at putting the pitot tube in not parallel but across the air stream leaving two ends to put my carb pipes onto, then from this info drilling and tapping a hole to put a main jet into.

do you guys think this would be a good idea? Or do you think the pitot would have to be parallel to the airstream for this to work?? Or not work at all?? 

[slingy1157]

Ok, carbs are pretty much stock,  but, because of the increased fuel pressure, the fuel level rises in the bowls, so you need to reduce the fuel height, usually by about 2mm.

So do the usual turn carbs up side down, take bowls off, then with them still up side down, measure from the carb bowl gasket surface to the highest point on the float. should be about 13.5mm stock I think, but what ever it is, first check all 4 are the same, then bend the little tab in the centre of the float down untill you raise each float to 15.5mm (if starting at the example measurement of 13.5mm). This will help stop them from flooding and keep fueling nearer the stock jetting.

[majortom4]

Ok brilliant. Thanks for the answer and the explanation :-) will get that done before re-fitting them. 

[slingy1157]

Also lockwire or zippy tie the floatbowls vent hoses and fuel pipes to stop it all blowing apart with boost. Easier doing it with carbs off as very fiddly

[majortom4]

Also lockwire or zippy tie the floatbowls vent hoses and fuel pipes to stop it all blowing apart with boost. Easier doing it with carbs off as very fiddly

yer going to lock wire those. Got a lot of lockwiring and jubilee clipping and stuff to do...... Zip ties have become my best friend as well haha.

[slingy1157]

You need to get the fuel pressure as low as possible. You can even take the spring out of the fuel pressure regulator as just the internal restrictions will give 1.5 to  2 psi fuel pressure which is on the limit of what the float valves can hold safely. And remember, the higher the fuel pressure the higher the fuel level will be in the carbs and the more adjustment to float height you'll need

[majortom4]

Yer I have adjusted the idle fuel pressure on the regulator to under 2psi. 

Do you know anything about the pitot tube setup?? 

[majortom4]

And wow I think the hulk has tightened the screws on my float bowls.....

[slingy1157]

Long be afraid to hit screw driver with hammer repeatedidly while trying to turn to loosen, or use an impact driver. Also a good idea to replace all fasteners on the carbs with socket head screws as they will be apart ALOT before your done.

[Fula28]

Long be afraid to hit screw driver with hammer repeatedidly while trying to turn to loosen, or use an impact driver. Also a good idea to replace all fasteners on the carbs with socket head screws as they will be apart ALOT before your done.

So true! The fasteners get a right Royal workout! Mind you very satisfying when sorted.

[slingy1157]

Pitot design is black magic voodoo shit but basics seem to be.

Keep away from turbulent area's such as elbows or turbo outlet, and generally the  pitot running parallel with the uppipe seem to work better. Like you say, I would use a 10 mm pitot, then block the end and drill maybe a 3mm hole in it. Then this can be opened up 0.5 mm at a time untill you find a size that works for your system. 

This is what isrecommended by Unclebobs Turbo's. Google it, it's a very good resource.

[slingy1157]

So true! The fasteners get a right Royal workout! Mind you very satisfying when sorted.

I wwouldn't know,  I spat the dummy and went efi before I got mine sorted haha

[Gixer1460]

Pretty sure someone on the old site used the 'cross port - single tube - twin ends' arrangement and found it un-satisfactory and so reverted to the 'normal' bent tube pitot. Probably didn't work as forcing air to make sharp turns loses momentum and pressure. I'd stick with tried and tested - likewise a main jet of say 300 is maybe a 1/4 or less area of a 6mm dia. pitot which is a normal size (or bigger) - that single pitot has to pressurise 4No. carb bowls - that's a lot of surface area!