TPS/Carb jetting/Cans!!

[Griff1977]

Griff, was it CM ?

Hi mate, I wasnt ignoring you first time, but didnt want to get into a personal/direct attack of the dyno chap. Not CM but CG! I think he was just Power Commander experienced and went for the easy option with me due lack of carb/Firestorm experience. Griff

[edds11]

not at grimsby then

[Griff1977]

Any chance you can send those 48#s back mate lol I can bung them in the carbs I am selling I took them from the spare set

Sent from my GT-I9300 using Tapatalk 2

Hahaha, no worries mate. Just PM me your address. Ta, Griff.

[Griff1977]

not at grimsby then

PM'd, Griff

[edds11]

the reason for the question was because a good friend of mine was having some fairly delicate work done at the time I read your post, I was in 2 minds to tell him to postone, but glad it wasn't, thanks anyway

[Griff1977]

the reason for the question was because a good friend of mine was having some fairly delicate work done at the time I read your post, I was in 2 minds to tell him to postone, but glad it wasn't, thanks anyway

Cool.

[Griff1977]

You may find yourself going back to the 48's mixture on the 50's is roughly 1.1/4 front 1.5 rear. As for adjusting them with the bike running, you need the proper tool. A right angled ratcheting screwdriver. Even then it's a struggle.

I use one of these.








Did you re-sync the carbs/carb balance after all those changes.

I could feel your sense of achievement and enjoyment you had in your post. You do realise you will be tweaking all the time now

(:-})

Just looking around on tinterweb, cannee find your one anywhere - most right angled ratchets are quite chunky.

Do you remember where you get it from?

Ill keep looking!!

Yes, checked sync, didnt need adjustment, but if I change mixture again (different from front to back I guess) then prob need some adjustment.

Griff

[edds11]

search for ' carb' adjusting tools'

[VTRDark]

Mine came from the States, it's a motion pro. Got a mate to pick it up while on holiday there.

Some have had luck with this style.
http://www.ebay.co.uk/itm/460mm-LONG-MO ... 2a15b717c4
But I can't see how.

I used to have a 90 degree Bevel Screwdriver from carbtune
http://www.carbtune.com/
And struggled badly with that.

The front carb is not so bad but the rear is real tight with the carb coolant hose in the way and stuff. As you can see mine is a lot more shallow than the others and the bits themselves are half the depth of standard ones. I still struggle but it is possible to make adjustments.

You should check the carbs are synced after any change. Mixture adjustment wont be so bad, but changing jets about or adjusting needles usually makes a difference.

(:-})

[Griff1977]

Ah, All I can find is this £50 one on ebay:

http://www.ebay.co.uk/itm/Motorcycle-90 ... 564ca4607b

Oh well I will keep looking!

Griff

[tony.mon]

Does anyone have the Main Air Jet drills mentioned earlier in this thread?
The FP jet kit I bought didn't have these, and it's worth a try.

Just for a borrow, you can have them back once drilled, of course.

[VTRDark]

No one that I know of here or on the hawk site has done it. This is why I'm very curious as to the effects and am considering it on some spare carbs myself. There is one downside that I thought of the other day tho. I would like to have a flow commander at some stage and drilling the MAJ will hinder this as they give you plugs to fit into the MAJ that the hose attaches to.

(:-})

[Griff1977]

Does anyone have the Main Air Jet drills mentioned earlier in this thread?
The FP jet kit I bought didn't have these, and it's worth a try.

Just for a borrow, you can have them back once drilled, of course.

Tony

This is the kit that I have (see below), they call it the FP 1.7 RK, and you get the drills supplied.

They are: fr1.4mm, rr1.1mm

I will happily lend them to you, no probs, but I am keen to commit myself first, and then I will give you a shout.

Maybe hoping to do it this week (possibly). If you havent heard from me for a while, then give me a nudge!!

Or, I believe they are classed as jewellers drill bits, so try these:
http://www.ebay.co.uk/itm/Single-metric ... 3a7aaae333

Or, these: http://www.ebay.co.uk/itm/Single-metric ... 3ccc86a1ba

At least you know they will be virgin, untouched before you, and hence, perfect! I guess tolerance is important here when we are talking about tenths of a mm?

Griff

[Griff1977]

Nice one, that's useful info, especially the bit regarding drilling right through to the carb bowl which was the bit I did not know about regarding drilling. If any drilling is to be done then make sure the diaphragm slide and needle is removed and also the float, main jet and emulsion tube from the float bowl before any drilling is commenced. I'm very tempted to give it a go on my spare carbs. And note that the drill bits are different sizes for each carb just like the main jets.

I agree with Tony by adding more air it may require larger main jets to balance out the A/F ratio but not 100% convinced. It's seems logical, more air=more fuel required to balance out the A/F ratio. But the reason I am not 100% convinced is because with the HRC kit that is designed to run with no airbox (much more air) the main jet sizes are in the 150's-160's, smaller than standard. The other clue that hints that it may require small is that in the FP CRB-H77-1.7-RK kit they don't supply a 188 main as they do with the CRB-H77-1.1-TI. Just seems to be odd to me why they leave that out.

I'm not sure how drilling the main air jets only affects top end. I would have thought it would add some top end as FP say but not just top end but all the way through the range. I may be wrong as I have no experience with drilling these carbs and how it effects the jetting side of things as to whether it requires smaller or larger mains. I would like to think it would be smaller as this would save fuel or is that just wishful thinking You never know you may discover a way if saving more fuel. Mmmm interesting.

Nice to see Factory Pro are being helpful and answering any questions. Thanks for sharing that.

And here is a pic of the Main Air Jet on our carbs.



(:-})

Carl, So, this MAJ! Below it (I think, attached), (in the float bowl) is the emulsion tube and then the main jet, right? And I take it then that the MAJ is fixed solid to the carb and so I would drill it in situ (not carbs left on bike, that would be ridiculous, but the main air jet staying on the carbs?)? I am just coming out with what is in my mind but if you have spare carbs 'to hand' then poss in a better position to answer these moron Qs!?

I want to make a change to the adjustable clip height on the needle - at '0' position at present (lean), will aim for #4 (down from blunt end) position, as I am sticking with the BMC filter and feel it needs a little more richness mid range, although it rides fine, maybe a slight slight hesitation - nowhere near how K & N was a few months ago, and the BMC was the other week! That was ridiculous, basically my engine was stalling with fuel starvation from 2500-6000!!! (before any dyno/tweaking, just lobbing filter in, with stock settings).

Anyway, regards, Griff

[VTRDark]

Carl, So, this MAJ! Below it (I think, attached), (in the float bowl) is the emulsion tube and then the main jet, right?

I believe so yes.

The MAJ can be pulled out as I think as this is what one has to do if fitting a flow commander as they supply bits to replace them with an attachment for a pipe. I think they would be hard to pull out and would probably get damaged thou. So best to leave in situ.


Make sure you remove the slide and needles before commencing any drilling with carbs off and stripped down held as straight as poss on a work bench or something. You want a nice straight cut.

How to remove needles from slides
http://www.vtr1000.org/phpBB3/viewtopic.php?f=9&t=25163

Carb strip down
http://www.vtr1000.org/phpBB3/viewtopic.php?f=9&t=25177

The fun bit is putting the springs back in the cap and diaphragm. Smear a little grease around the rim of where the diaphragm rubber sits to hold the edge in place. Then compress the long spring into the cap, hold it with your thumbs and hold it as close over the carb as poss and release the spring into position (still holding the cap) and then screw back down in place. A little fiddly at first but gets easier with practise. Just be carful not tp pinch the edge of the diaphragm rubber when re-sating the cap.

(:-})