can I fit bike carbs to 1.8 cvh without problems ? reading most of the threads again I am now confused, I don't have a prob making a mainfold & already have a electronic fuel pump, bit that confuse me
if fitting none injection carbs do i need a fuel return?
do none injection ones have tps ?
do they need a ecu ?
its needs to be very locost !
which ones are the Best, easy to use ?
thanks
steve

Yup, you definately sound confused!

Your existing fuel pump might be controled by the ECU so you might need to re-wire that.

All carbs work at much lower pressures that Injection so a fuel pressure regulator would be needed (not sure if they require a return or not). Should you use the existing injection pump, it might be cheeper to use the bike setup as this would provide the correct volume and pressure.

Carbs do not have a Throttle Position Sensor, this is only needed for injection system ECU's to know the "Throttle Posistion" and adjust its internal maps.

You will also need to consider what contols your spark timing should you do away with the current injection system and its ECU

sorry more info for you
at the min I have 1.3 crossflow to be changed to a cvh 1.8
electric fuel pump not controll with ecu & yes pressure reg fitted

So was the 1.8 injected or running carbs?

If its carbs then the pressure will probably be fine,

If it was running injection then the pump and regulator will be set to too high a pressure and no doubt un-adjustable.

If the fuel pressure is too hight for carbs the float valves can't shut off against the pump and this floods the carbs.

yet more info
1.8 cvh J reg running on carb
Fuel pump at min running a 1.3 crossflow with pressure reg fitted
Cheers
steve

I do believe 'Surrey Dave' is your man. He has successfully got a 1.8cvh running with bike carbs and megajolt I believe.

hth,
Andy

quote:

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Originally posted by andylancaster3000
I do believe 'Surrey Dave' is your man. He has successfully got a 1.8cvh running with bike carbs and megajolt I believe.

hth,
Andy

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I'd say you'd definately need megajolt to contol the advance and retard of the timing properly

It may be possible to revert to an older vacume advance type dizzy although this will always be a comprimise to megajolt, it does make a massive difference.

Your prob looking at about £100 for megajolt.

Carbs are no problem. Your existing fuel pump and regulator should work fine. You can use the standard distributor setup, but you'll need to either supply it with a vacuum signal or disable the vacuum system. In the past with Crossflow stuff, I've just pulled the diaphragm off the dizzy and welded the vacuum advance rod to the diaphragm housing, crude but effective. You should still have your dynamic advance set up on a rolling road though for best performance.

Carbs can and do sometimes have a TPS (throttle position sensor) fitted. Most more recent bike ones do as 3D ECU controlled ignition (uses rpm and either map or TPS to determine engine load and hence required advance setting) Tends to result in smoother running and lower emissions.

I have honda blackbird carbs on my zetec and have successfully connected and calibrated the honda TPS to work with my GEMS 3D ECU. However no ECU and the TPS will be redundant. The megajolt units can be configured to use either a TPS or a MAP sensor and from what I have seen are fairly cheap to build or buy. As far as fuel pressure goes, bike carbs require "very little" as on the bike they are often gravity fed from the tank above with no pump involved. You are best to use a motorbike fuel pump from something like a carb'd R1, R6 or other 600-1000cc sports bike, they pump until they sense the needle valves closing in the carbs (back pressure in the fuel line) and slow down / stop pumping as required, so you won't need a pressure regulator.

There are a fair number of us on here using bike carbs now so you shouldn't be short of help. I'd also recommend talking to Steve Bogg of Bogg Bros fame, very helpful bloke and knows his stuff when it comes to bike carbs and car engines.

http://www.boggbros.co.uk/contact.html

And reading the article in this months PPC

[Edited on 25/2/06 by givemethebighammer]

Many thanks
I wanted to fit bike carbs to get away from all the sensors & size of the manifold of the cvh
Think the way to go then is save up and get bike carbs and megajolt
So, things needed for megajolt
Coil packs
EDIS
Is the CPS & crack pulley ok to used from the cvh ?
Does the megajolt rely on TPS/MAP sensor ? will the carbs require one of the sensors ?
Thanks again
Steve

It'll have to be a TPS on the carbs really as setting up a MAP sensor with multiple carbs is supposed to be a real pain. If you go for late model Yamaha R1 or Honda CBR (600, 900, 1000) then they will have the TPS attached (just make sure its still there when you buy them !)

The standard CPS should be OK.

[Edited on 25/2/06 by givemethebighammer]

later R1 will injection won't it ? or will this work ? locost

Sorry, should have explained. Not that late. Early model carb'd R1 and YZF bikes may not have had the TPS (the early hondas didn't). You could fuel inject your carb using motorbike throttle bodies, but then the level of complexity goes up. Look for a set of carbs from about 1996 / 97 and check they have a TPS. My 1997 honda blackbird ones did.

don't get confused between carbs and throttle bodies. They may look the same but operate differently.

Any carbs with a 97' or newer vintage will probably come with a TPS that can be used with a megajolt etc etc.....You will not/can but is not worth the effort, run them with either a car electronic or mechanical fuel pump as the pressure is too high....you must fit a bike fuel pump but these are cheap at £20 of gay bay....There is nothing wrong with using the bike carbs with a normal dizzy setup and they will work fine. Don't be fooled into thinking that these are a cheap and cheerfull option though, if you want a proper setup its realisticaly gonna cost you about £300 by the time you've got it running....nowhere near as expensive as webbers though and they give arguably better performance and require absolutely no fiddling to work un like webbers! HTH and if you've got any questions send me a u2u....Oli.