Bike Carbs on 1.7 b17

[Sparco_Tom]

I have used the search function but it isnt throwing up much.
How many people run bike carbs or currently fitting bike carbs?
Interested in peoples spec and ideas.

[magnumpi]

On a standard fit volvo 1.7 you mean? If so probably none as it wouldn't really be an improvement, it would just drink more fuel.

[volvosneverdie]

On a standard fit volvo 1.7 you mean? If so probably none as it wouldn't really be an improvement, it would just drink more fuel.

there would be a power increase surely?

R1 carbs would be close enough for a 1700. But youd need a one off inlet manifold, a pump near the tank, a managment system (megajolt etc) and some rolling road time to set it all up.

For the money youd spend, itd be a lot cheaper and a lot more powers just dropping an F7R in the front.

And welcome to the forum mate.

[magnumpi]

I'll be honest i'm not sure if they would improve power or not .

I'd imagine they would marginally but only on full chat, around town driving i'd doubt you'd notice any difference except making it harder to drive. I base that purely on my experience of big twin carbs on the Beetle though. It's all relative really, it wouldn't be woth IMO putting on bike carbs unless you are going to change the cam, port polish the heads etc, by which time as you've said you may aswell just go for a Valver conversion.

[CBA]

DO IT DO IT DO IT!!!
If you do it i'll do it!!

I think you'll need to get a replacement ignition to properly use the extra fuel, put trumpets on the carbs ....

then it's time for a cam, but (I'd) expect 105BHP+ with properly set up bike carbs and a "Real" distributor setup without an aggresssive cam.

[volvosneverdie]

I base that purely on my experience of big twin carbs on the Beetle though. It.

Were you running any managment man? or just the big carbs?
Same pump?

[magnumpi]

I base that purely on my experience of big twin carbs on the Beetle though. It.

Were you running any managment man? or just the big carbs?
Same pump?

1776cc with ported and polished heads, lairy cam, Webber Twin 40's, facet electronic fuel pump no regulator no electronic gubbins at all except the old points were replaced with a Petronix Flame thrower.

Like i say though thats pretty irrelivant here as it's not really the same thing

By all means go for it it if you fancy the sound of bike varbs etc, but i think the power output guesses are a bit optomistic?

[theo2468]

i doubt there would be much of a performance boost cause theres nothing the 1.7 can do with all that air, it doesnt need it.
With all the hassle of getting that to run properly and money you may aswell do what everyones said,the valver conversion

[sven360]

I agree with the yoof above.

Over fuelling can be as bad as lack of.

[filthyjohn]

Bike carbs do a good job of supplying a good AFR, they'd improve a 1.7 all across the rev range, but it wouldn't be optimised for driveability or economy. That said, the R1 carbs on my manta are great, though we're talking more like 180hp than 105.

[Sparco_Tom]

I have carbed and throttle bodies soo many engines. Setting up and tuning to get them to run correctly wouldn't be an issue. Also being a specialist precision machinist i would be making everything myself and setting up myself. I was looking at using r1 carbs as they have shown good results across a number of engines. As for a cam i would source something wild or machine up my own as a last resort. Long trumpets on the carbs and a manifold to match should increase low down torque after the jet needles have been opened up to around 1.8mm. I am not naive and deluded i appreciate there are very small power gains from these engines but the noise and satisfaction having something different does it for me.
Fuel economy and drive-ability isn't an issue as i only use the 340 as a cheap and different skid car ( fed up of BMW's/jap rubbish)