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Bike carbs
Stuart_B - 7/3/08 at 01:17 PM

Hi, i am going to be starting the bike carb conversion soon, and i know that you are ment to drill out the main jet, but is it better to get a Dynojet kit for my carbs Cbr600 fx carbs? going to be running on a 1.6 pinto
as well drilling the main jet out is it the same as the Dynojet kit does?

thanks

stuart

hardassfunk - 7/3/08 at 02:26 PM

drilling out the main jet is a waste of time IMO .If you buy a Dynojet kit they come with new needles and usually 2 difffernt jet sizes,only problem is theyre expensive but you can buy individual parts

triumphdave - 7/3/08 at 02:43 PM

Drilled mine out on both of my conversions,if you go too big solder them up and have another go.

DarrenW - 7/3/08 at 02:46 PM

I drilled my ZZR1100 carbs for 2.0 pinto and they were fine after rolling road. You dont always have to drill out the jets - check what size are fitted first (ideally measure).

Ive heard sometimes you need dynojet - sometimes you dont. I would guess if you get Dave at Boggs to set them up he will get round the need. Best to try without first.

My pinto responded well to magajolt as well - worth considering unless you have plans for bigger engine in the future.

Stuart_B - 7/3/08 at 03:35 PM

as i am running 1.6 pinto, i do not want to put megajolt on it, as it will possible end up with a bike lump in it.

the problem is Boggs is so far away from me, and i will me sarting to convert it to bike carbs soon and i am not to sure what to do first on setting the carbs up, what size are cbr600 fx carbs jets??

triumphdave - 7/3/08 at 06:20 PM

The jet sizes are stamped on the jets.160=1.6mm

UncleFista - 7/3/08 at 08:21 PM

quote:
Originally posted by hardassfunk
drilling out the main jet is a waste of time IMO .If you buy a Dynojet kit they come with new needles and usually 2 difffernt jet sizes,only problem is theyre expensive but you can buy individual parts


So, either a waste of time or a waste of money, I suppose you pays yer money (or not) and takes yer choice

RichardK - 7/3/08 at 09:03 PM

I drilled mine out to 1.6 and seems to idle nice but haven't had it dyno'd yet, but think the dyno will be beneficial to get my megajolt setup right.

Pictures in my gallery use the link below if you can be arsed

Rich

DarrenW - 7/3/08 at 09:09 PM

If you are going BEC i wouldnt bother with bike carb conversion. You will need a rolling road set up to get the carbs optimised. My car was running great at first - or so i thought. It was in fact way to lean and at risk of causing damage. When you factor in full cost of conversion you are spending a fair lump of the BEC budget.

David Jenkins - 7/3/08 at 10:15 PM

quote:
Originally posted by DarrenW
When you factor in full cost of conversion you are spending a fair lump of the BEC budget.


I can't agree with that statement!

So far I've spent barely £100 on my bike carb conversion - I will admit to saving money on my DIY manifold by fabricating it myself and getting an expert to weld it for nowt (thanks Paul), but if I hadn't had that option I would have made a steel one entirely by myself. Within that budget I have also fitted a fuel pump and regulator, replaced the entire fuel line, and fitted a blanking plate instead of the old mechanical fuel pump. I have also fitted a safety 'roll-over' pump/ignition cut-out switch.

Although nothing has been properly set up yet, I have already seen a far better tick-over at around 750rpm, instead of the 1100rpm I could only ever manage on the old down-draft Weber. The engine also sounds a lot 'happier', if that's not a daft thing to say. I will have to check the mixture at higher revs (I've already checked it with a Colortune at tick-over) before I get on with regular driving. Even if I pay another £200 at a rolling road, it's still cheaper - and I'd probably have to do that with a bike engine anyway.

Fitting a bike engine costs a lot more than the price of the engine - there's the propshaft to be bought, and all the other odds and sods. And I like to have reverse gear!

[Edited on 8/3/08 by David Jenkins]

Stuart_B - 8/3/08 at 09:52 AM

Reseve gear does sound good.
is the frist job is too make the manifold?

stuart

Stuart_B - 8/3/08 at 09:54 AM

hi rich what carbs are you using?

stuart

jacko - 8/3/08 at 07:45 PM

HI i have zx9r carbs on my pinto .
I made my manifold my self .
I drilled my jets out to 1.7mm you don't need to buy new jets
there is a lot of info on this site about bike carbs do a search under my name [ Jacko ]
have a look in my photos under zx9r + manifold it may help you if you are making a manifold .
And as Darren says get it on a rolling road before driving the car far i had mine done at Bogg Brouthers and glad i did saved my engine it was running week at high revs before i had it done
Jacko

RichardK - 9/3/08 at 10:38 PM

Honda CB600 Hornet W reg
Cheers Rich