V1000 with VHB30's. Jetting? Fixed so far!

[Tom H]

I just converted my Ambo to a V1000 with 5spd trans. and rear end.

The carbs are VHB30 with 30 manifolds, 60 slides, 55 pilots and 130 mains. The set I'm using came with 60 slides. 55 pilots and 125 mains. I changed the mains to 130 per Guzziology.

The manual says to use 40 slides, 50 pilot and 125 mains. If I read it correctly.

Right now the bike runs nice, not as much low end power as I had hoped for. It feels a LITTLE better than my Eldo, but not even close to my EVT 1100 FI. It starts fine, although I DO have to use the enrichener, never had to with my Eldo or Ambo, I am told this is normal for a V1000. So far the plugs look decent and no smell of gas on them.

I would like to know what slides, mains and pilots are the normal for the VHB30's with a V1000? What do you use??

Thank you,
Tom

[LesP]

What about the V9 (iirc) needles ? (Corrected from K9)

#
That manual jetting ( iirc Charlie M told me the stock 948 jetting) but used the original VHB29's  looks to be what I used (but did not record it)

I modified new slides to suit.
40 slides.
50 pliots.
V9 needles.
125 mains.

A #60 slide would be quite lean compared to the factory recommendation.

[Tom H]

Running V9 needles at 2nd notch.

Add on:

Running Eldo distributor with timing at 2 deg BDC. Should I move it up to the Eldo 5 deg?

Slide? If the manual calls for the 40 slide and I'm running the 60 slide. Should I be looking at more of a Eldo jetting with richer main jets? Maybe my 125 or 130 are too lean?

Tom

[LesP]

I am sure an expert will be along shortly to answer that (A lean slide is going to make it interesting off the bottom) based on I haven't even ridden a Moto Guzzi (or road jet checked one (yet)

I can't see a bigger main doing much coming off idle (fwiw)
The slides are not cheap to buy I might add.

[80CX100]

Running V9 needles at 2nd notch.

Add on:

Running Eldo distributor with timing at 2 deg BDC. Should I move it up to the Eldo 5 deg?

Slide? If the manual calls for the 40 slide and I'm running the 60 slide. Should I be looking at more of a Eldo jetting with richer main jets? Maybe my 125 or 130 are too lean?

Tom

     Good luck trying to find the 40 slides, I read the same thing in Guzziology, but I was told by a few suppliers/sources they were unavailable when I rebuilt and set up the VHB30's on my CX100 (same engine as yours) 7 yrs ago.

     I was doing a lot of different work on the bike at that time, but my impression was that the best change in the fueling/running of the bike was when I cleaned and replaced everything in the electrical/ignition systems.

     The bike has a set of large K&N pods & Lafranconis and here's what I believe my final jetting to be, it runs nice and strong.

      60 slides
      V9 needle middle slot
      265 atomizer
      140 main
      52 Pilot

      fwiw good luck

      Kelly

[moto]

Changing the main jet won't help in that range right off idle.* What you need is a different slide. But you can modify your own slides to get a lower number equivalent. What you need to do is file (or machine) off the bottom of the slide, being very careful to keep things square. (Scribe a reference line before you start filing.) I took about 0.7 mm off the bottom of mine and this improved the performance off idle. This procedure was suggested by Pete Roper back in 2008 when he roamed these parts. Be careful and consider doing this in stages, checking results as you go . You can't put the material back on.

Moto

*Google for the Dellorto Carburetor Tuning Manual to understand why.

[LesP]

     Good luck trying to find the 40 slides...

https://www.ebay.com.au/itm/Dellorto-7454-VHB-Square-Throttle-Slide-Size-40-Benelli-Aermacchi-Ducati-Laverda/163439285373

I am not sure how you remove material to make a #60 slide (6 mm) into a #40 (4 mm)
There was a page on TOT where a dude in Japan (iirc) added a machined plate to make a #60 into a #40.

If you are tempted to buy off BSAnut you need to make sure he sends you the part you are paying for, in my case he sent the wrong parts ($150+) then said I was lying and he did not even make a slide as I described then listed the exact same part a few weeks later.
When I asked, how about fixing your $%^& up he offered me $15 which I politely told him to stick up his jacksy.

As posted elsewhere I was not to worried as the gods were smiling without me knowing it and got the 88 mm cylinders afterwards and that meant I could machine the 'wrong slides into the ones I wanted.

The other saving grace was many years ago he listed a NOS INOX stainless steel front fender/ mudguard and stays on eBay between Christmas day and New Years day (To suit my 1973 Ducati 750GT)
I bid NZ$427 for it, there were only a few bidders and won it for what would have been under US$100 posted.
They were NOS unobtainium then, now they are unobtainium ++ and probably cost the same as MG Gilardoni cylinder kits x 2 if you could find one.
Thanks BSAnumbNut, I forgive you. 
 

[moto]

https://www.ebay.com.au/itm/Dellorto-7454-VHB-Square-Throttle-Slide-Size-40-Benelli-Aermacchi-Ducati-Laverda/163439285373

I am not sure how you remove material to make a #60 slide (6 mm) into a #40 (4 mm)
There was a page on TOT where a dude in Japan (iirc) added a machined plate to make a #60 into a #40.

The relevant measurement, as I recall, is the vertical difference between the bottoms of the longer and the shorter flat faces of the slide (one facing the intake port and the other facing the carburetor air filter). By removing material from the longer one you can decrease that measurement. As a result, the whole slide sits 0.7 mm lower in the carburetor (in my case), which in itself has no effect on its operation.

Moto

[Tom H]

A few years ago I bought a pair of slides from him. They were supposed to fit my Eldo VHB29's. They were 40 slides. You ever see black smoke out the pipe when you start up, it was amazing. He did give me a full refund after I explained that they were not stock for the Eldo. Now I sorta wish I kept them.

I have read the tuning guide, I get the basics like a 40 will pull more fuel than a 60, Pilot is in control up to about 1/2 or was it 2/3 throttle then the main takes over. And then throw in the needle a V5 or V9 and then the notch position and ......... Then my head explodes

The bike runs OK as is. I need to put more miles on it. Then I want to try what is suggested here. So far it looks like my pilot is in line, but need a bigger main.

More suggestions please!
Tom

[LesP]

A few years ago I bought a pair of slides from him. They were supposed to fit my Eldo VHB29's. They were 40 slides. You ever see black smoke out the pipe when you start up, it was amazing. He did give me a full refund after I explained that they were not stock for the Eldo. Now I sorta wish I kept them.

Tom

Holy cow, that is what happened to me, I bought the supposed to be #60's for my stock VHB29's.
Basically I was expected to post them back to the USA from Australia at my cost and of course having cost some $150 they would need insurance so probably $50 to post so it was not worth it.......... Only when he got them back would he do anything.
I gave up.... but yes it worked out in the end as I moved to the next drama which was the broken 948 cylinders and 9 months for HMB Guzzi to replace them after I had to foot the bill of $126 to post them back to Germany.

I am not sure why I had to machine them (if they were #40's) now so will remove one and measure the step tomorrow, iirc a #40 has a 4 mm step, 6 mm on the #60.
I guess I should be grateful they were available as a new item and have the machine tools to modify parts, it is one time where procrastinating was a bonus having not machined them into #60's straight away.

[80CX100]

More suggestions please!
Tom

     Have you got the oem velocity stacks installed? One of my bikes was missing those and when I researched it, learned that without the velocity stacks, overall performance would suffer, especially down low.

     Are the needle seats new/or in good shape, apparently when they get worn from the needle rattling around inside, the flow and air velocity suffers.

     Same thing with the enricher plunger, I know there's a rubber seal at the bottom, possibly an O ring on the top iirc, as well as the top paper gasket, if those parts of the carb don't seal well, apparently overall performance suffers, fwiw.

     Good luck

     Kelly

[Two Checks]

Both my SPII and Cal III had 130 mains and would stumble at WFO.
Put the needle on notch 2 left the 265 atomizers in with 50 pilots and 142 mains. Left the slides alone-don't know what they are. Stock airbox.
It pulls hard to red line. Plugs still look a little lean. I think its a combination of E10 fuel and I'm at 440' MSL.
That also worked on my 850T and a friend's G5.

[Tom H]

The velocity stacks are stock kinda bell shaped from the Ambo, I do have a set for the VHB30's that are the straight looking ones.

New V9 needle, but the atomizer is what each came with. I tried gently tapping them out (I have removed them on my 29's before), didn't want to move and didn't want to damage them.

The slides have wear on the finish, but no scratches. They actually look a bit better than the ones the 750 was running.

The enrichener has new slides in them.

I was reading Guzziology a bit more. For the V1000 in a G5, CX ect.. The jets and needle are the same, but the slide and the air mixture screw are different. Also the T 850's are supposed to run the 40 slide as well, but my 850 Eldo is supposed to have a 60. Same CC bikes?? With the 40 slides, you do use smaller jets.

On the air mix screw. I did change them to the short tip, they had the long tip. I got it running well on the short tip and decided to see what happens with the long tip. I adjusted the long tip the same turns and it didn't idle as well as the shorts. Even tried it at two turns per the book. If I played some more, maybe they would have been fine. I put the short tips back in at least for now.

Thank you for the suggestions so far!!
Tom

[80CX100]

The velocity stacks are stock kinda bell shaped from the Ambo, I do have a set for the VHB30's that are the straight looking ones.

     I'm not familiar with the stacks from the Ambo; are they shorter and wider?

     I've picked up a set of the oem straight velocity stacks for the bike that was missing them, I haven't used them yet, but from reading on it I get the impression that the long narrow straight ones help increase air flow and performance a lot on those carbs, they've got literally no intake mouth on them at all.

     I know what a pita, carb, stack, boot, air box connections are on those engines/bikes;(why I went to pods); but if the velocity stacks from your Ambo are much shorter and wider, and it was easily doable, I'd swap them and see what happens, fwiw ymmv

     good luck

     Kelly

[Tom H]

I have Uni Filter pods on it now. I "think" I would like to use the stock air box at some point, but then it HAS to use the original velocity stacks. The stock box (with K&N filter) actually helped my 750 with some top end issues as well as jetting changes.

I know I do not have anything near a 50 pilot, it has 55. I may have 142 mains, need to dig again. I think I will try this and see what happens.

Thanks again!!!!!
Tom

[Two Checks]

Being as you have pods the 55 pilots just may work. The 142s will probably be fine or may need to go a bit fatter. You be the judge!

[moto]

You can buy new cutaway-40 slides for $62 each, apparently, here: 

https://www.eurojamb.com/products/new-7454-dellorto-vhb-throttle-slide-size-40-moto-guzzi-ducati

They are said to be in production again by Dellorto. (There is also a listing for a single such slide on Ebay.)

If you want to modify a 60 to make a 40, you can read about the two possible methods here (one by adding a plate, the other by filing):

http://www.thisoldtractor.com/moto_guzzi_loopframe_carburetor_throttle_slides_-_change_a_60_into_a_40.html

When I used the filing method, I was richening up a 40 for my T3, so I only removed a small amount of material, taking off 0.7mm to make it into a 33. Taking off 2mm to change a 60 to a 40 may also make a 2mm change to the position of the needle with respect to the needle valve it sits in. (I considered this at the time.) If you carefully examine the parts you may be able to figure out how much this matters before you start filing.* The needle has both cylindrical and conical (tapering) sections, and you can measure where they start and stop and what the diameters of the cylindrical sections are.

As for the choice of a 40 over a 60 for your engine, the two-page Carburetor Jetting Table in Guzziology (version 5.1, 2001) shows a line for "Convert, G5" which both have "V1000" on the side panel, so I suppose that's the motor you have. The listed U.S. specs include a size 60 slide. But looking one line up in the table I see the very similar "CX 100, 1000 SP" European specification: the only differences are the use of a size 40 slide and the short-taper mixture screw (which you already have). After considering the other specifications for the VHB-carburated big twins in that table, I'd guess the size 40 was specified precisely to give the motor more fuel for better performance in the 1/8-3/8 range of the throttle, compared with the compromise needed for EPA approval in the U.S.

If I were addressing your originally-stated symptoms, I'd buy the size 40's as soon as I saw this message!

Moto

* (EDIT) I expect you might conclude that raising the needle by one groove would be appropriate for a 2mm change in the slide face. But, again, I would be carefully measuring things instead of guessing if it were my project.

[Tom H]

Moto thank you for the answer. I was looking at the Guzziology table for the set up. The interesting part is that the answers so far here say it needs a bigger main. Also thanks for the heads up on the 40 slides. I may just grab a set.

Edit: I don't know for sure what this engine came out of or it's exact year. The letters are VG and was told it was a V1000.


But.......

For the time being until I get a feel for the engine and how it works/feels compared to my other bikes, I think I now have the very close setup.

I did have a set of 140 mains. In they went.
55 pilots
60 slides
needle at second notch
short tip air screws
Uni pods and Loop velocity stacks.

Seemed to start from cold a bit easier. Still needed choke. Seemed to idle fine and now can give it a few revs cold without it trying to cough. Still need to let it warm a few moments before riding. BTW, temp in the garage was probably about 65 deg F.

I know the mains don't have a serious effect on the low end, but starting up at a light with a still cool (less than 3 minutes run time) engine was much smoother/easier. Giving it gas once going from the light was much smoother. Got on a freeway where I could hold it open in 5th and all felt pretty darn good. I tried holding it open then open the enrichener to see what would happen, the bike didn't like it. Only issue with W/O was a slight ummm..... stutter ummm.....not flat spot, ummmm.....like when I let a little off W/O, just a slight bit, it liked it just a tad better than W/O. Maybe 142?

It feels like my Eldo, a little better, at low throttle city speeds, nice pull. Freeway speed better than Eldo but still no where near the EVT. Now I don't feel like I'm having to force it to hold 70mph, it just does it. Perfect speed for a 1970 Loop. If I do want to run 75mph, it just does it without trying hard.

So I will ride it like this for a bit and see if and where I need to go on the jetting.

Thank you all VERY MUCH again for the numbers. Gave me real world numbers to try. Guxxiology is good, but I have found errors.

Thank you,
Tom

[Two Checks]

Yep, it still needs a little more main.
When you let off just a little and it picked up was the sign.

[moto-uno]

  If these are similar to my 29mm square slides , I find it surprising no on has mentioned the accelerator pumps .
When the entire jet assembly is removed , in the bottom there is a spring loaded plunger the gently ( very gently )
pushes a small quantity of fuel up the needle jet and on mine at least certainly has an effect on off idle shots of the
throttle . The spring is usually trashed , but I remember using one from a ball point pen (weak for sure , but it worked )
I love jetting carbs , tuning is almost as much fun as riding  , Peter

[Tom H]

Pump springs are intact and I think fine. The check ball does rattle.

I may try a 142, might have a 145 in a box? 140 is good so far.

Thanks again,
Tom

[moto-uno]

  You should be able to tell if you can get a small piece of metal down the needle jet tube (slide and all removed) and push
lightly on the plunger . It should have a slight resistance and return to it's original position . For instance , a welding rod and a
flat edge (ruler) on top of the carb , mark it see if after applying pressure it returns to the same position .  The check ball can
still be free , even if the plunger is stuck .   Peter

[LesP]

Or you could just have a look, give the parts a clean and reassemble.

 

[Tom H]

LesP, been there except pulling the ball. It blew through one way and not the other.

Tom

[LesP]

I did that Tom, then I thought, whats going on inside there then. 


I don't know if the police speedometer works properly yet and is the only thing not investigated.

[moto-uno]

  Okay , I'll bite , what is that ? looks kinda like a breather box . Peter

[Tom H]

  Okay , I'll bite , what is that ? looks kinda like a breather box . Peter

Yes it is a Loop breather. Can also be used on early Toniti's if I understand correctly.

Tom

[LesP]

Do you think I was surprised to see that rust could go down the smaller hole straight into the sump ,not that I thought there would be rust anyway from something that has its entry point above the spinning (oil throwing) crankshaft.

I went right through the VHB carburettors replacing anything that could be so they should be OK, the tin box will be replaced with something else.

[mtiberio]

Looks like you put thought into your trimming of the cutaway. Remember this, the needle may drop if left in the same clip position. You may need to go the the lowest notch to raise it back up. VHB slides are different than most as you cannot just shim the needs up.