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Rebuilt VHB 29 Carbs don't run real well

Where you been? Multiple FAILURES because of rings & valves, V85 & V7 range
Being a Guzzi wrench I hear about the failures, even ask the Tech Rep about them. Chinese
Does it say spa after the name anymore? Not since Aprilia takeover.
 
V700Steve said:
Where you been? Multiple FAILURES because of rings & valves, V85 & V7 range
Being a Guzzi wrench I hear about the failures, even ask the Tech Rep about them. Chinese
Does it say spa after the name anymore? Not since Aprilia takeover.
Click to expand...

Umm… re: S.p.A.

This is not because of Chinese parts.

Società per azioni (S.p.A.) is a legal designation of a corporation in Italy, meaning "company with stock shares".

Moto Guzzi has been a wholly owned subsidiary since Aprilia, which has also now been acquired by Piaggio, hence it is no longer a S.p.A. type corporation anymore as it doesn’t have shares of stock for sale anymore.

Piaggio owns it entirely.

Piaggio & C. S.p.A. is the parent company.

I am with Steve though on the V7/V85/C1400 platforms being plagued with Chinese parts and quality issues. It’s why I don’t own one of these models personally.

It is NOT a negative about the models themselves (I actually like them very much and would love to own them) but rather a frustration with issues that seem to plague these models for years now, and should never ever have reared their ugly heads after Moto Guzzi’s 100 years of motorcycle manufacturing experience.

Unfortunately the Chinese parts are so damn poor quality to me. I just really despise most Chinese products as they have ruined so many once great motorcycles.

I recently worked on a Benelli TK502. There is nothing Italian on this once great marque. It’s just cheap Chinese junk to me. Everything was cheap feeling, cheap looking, just cheap junk.

This is one thing I know for sure that Lannis and I agree on 100%. We do not like Chinese goods at all. They are crap.

Piaggio would do very well to stop using them as suppliers in my opinion.
 
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V700Steve said:
Where you been? Multiple FAILURES because of rings & valves, V85 & V7 range
Being a Guzzi wrench I hear about the failures, even ask the Tech Rep about them. Chinese
Does it say spa after the name anymore? Not since Aprilia takeover.
Click to expand...
Well, that's a bit disconcerting as I have a 2010 V7 Cafe.

Jason
 
JasonC said:
Well, that's a bit disconcerting as I have a 2010 V7 Cafe.

Jason
Click to expand...
Don't be. Just read up here and familiarize yourself with know issues, and take preventative steps against them. That's the best you can do. Many members have tens of thousands of miles or many more, on their V7/V9/V85/C1400 bikes.

Don't let this distress you, Just be proactive. That's the best advice.

Besides, I think the earlier ones seem to be more reliable than the later ones, at least to my brain. I could be wrong but...
 
I read through this post -- very interesting because I'm having an issue with my VHB's too -- a differnt issue.
I get a loud, very loud, backfire when I hit the starter button and the bike doesn't start. I didn't try it very long, afraid of engine damage.
I installed the VHBs to replace the SS1s on my 1969 V700 (maybe I should just have left the SS1s on, the bike ran ok then except the SS1's have a tendency to leak).
I went through the VHBs as carefully as I could (but I don't have a lot of carb experience). Cleaned them, replaced gaskets and o-rings, blew compressed air through the jets and orifices of the carbs and all seems ok. I didn't check to be sure the jets are correct (darn it).
I eyeballed the float levels, didn't check them precisely.
I'm using K&N pod filters with he proper velosity stacks per Bender's recommendation.
The valves are gapped properly as are the points and spark plugs. I tested the spark, looks strong.
The needle on the slide is set at second from the top.
I think I have the proper freeplay at the choke and throttle cables going into the carbs.
I surmise that it's backfiring because it's running way too lean or too rich. The backfire is so loud that it makes me think it's too lean?
I guess my next step is to take the carbs apart again and double check that I did everything correctly, but I'm hoping that, maybe, you guys might be able to give me some direction on what specifically to look for that would cause the backfiring?
Thanks! Sorry for the long post.
 
If you can, please take some photos of your setup on your motorcycle and post them.

I’m not sure I fully understand. The bike doesn’t start at all now , it just backfires? Or it only backfired if it does not start.

Please clarify.

If you remove and open your carbs back up, take some photos and I can help you with carburetors.

Thanks!
 
Moto-Uno said:
It sounds to me that you may have the plug leads reversed . Peter
Click to expand...
Wow, Moto-uno, you were right, I had the sparkplug leads reversed! Thanks! Feeling a little stupid, but I'll get over it. The bike still doesn't start but at least it's not backfiring when I try to start it.
 
scottmastrocinque said:
If you can, please take some photos of your setup on your motorcycle and post them.

I’m not sure I fully understand. The bike doesn’t start at all now , it just backfires? Or it only backfired if it does not start.

Please clarify.

If you remove and open your carbs back up, take some photos and I can help you with carburetors.

Thanks!
Click to expand...
Scottmastrocinque, I had the sparkplug leads reversed so I fixed that and it no longer backfires when I try to start it (to answer your question, it backfired but would not start). It still doesn't start, so I'll do some more work on it to see if I can figure it out. Attached are pictures of how things are setup......if you have any input that would be awesome. Thanks!!!
 

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robertx901 said:
Wow, Moto-uno, you were right, I had the sparkplug leads reversed! Thanks! Feeling a little stupid, but I'll get over it. The bike still doesn't start but at least it's not backfiring when I try to start it.
Click to expand...

I learned a very long time ago, on anything that is Left & Right, before I disconnect them, I just wrap a tiny red zip tie on the one that comes from the right. You will never make that mistake again, and colored zip ties are super cheap at Harbor Freight Tools.

In fact, I use colored zip ties (love the damn things really) all the time in my workshop. I often put one on the wire or tube or cable, and one of the same color on the component where it came from. Makes for very fast reassembly especially when I have waited often times, weeks, for parts to arrive.

Thank You Very Much for the pictures. I'll study your pictures when I have a free moment and comment then.

IMG 6506
 
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Thanks -- using zip ties sounds like a good idea, I'll try it out.
 
All I can say is check fuel and timing. When you can let us know which jets are being used. Once you get it going, I recommend taking the manifolds off, then having a welding shop build up a small area in the bend. Then to a machine shop and have that built up area flattened, then drilled and tapped so you can hook up some type of manometer device to synchronize the carbs. Take a look at 850T3 manifolds to see what I mean.
 
To add to the suggestions , I would turn the idle speed screws out a few turns and check that you still have some freeplay at the throttle cables where they enter the top of the carbs. If there's no freeplay , then the chokes won't be effective . The intake vacuum that would be strongest through the choke orifices is bled off by partially opened throttle slide . If it starts you can then play with the idle . Good luck. Peter
 
Moto-Uno said:
To add to the suggestions , I would turn the idle speed screws out a few turns and check that you still have some freeplay at the throttle cables where they enter the top of the carbs. If there's no freeplay , then the chokes won't be effective . The intake vacuum that would be strongest through the choke orifices is bled off by partially opened throttle slide . If it starts you can then play with the idle . Good luck. Peter
Click to expand...

And if idle is low, raise the slides before turning the idle stop screw in.
 
Thanks John Zibell and Moto-Uno -- I'll be working on it tomorrow, will let you know how it goes.
 
Robertx901,

Looking at your extermal pictures, I'm not seeing much to give me pause except the slash cut where the carb mates to the intake manifold. Is that slash open to the atmosphere? If so, it is a source of leakes galore. I presume that it is laying over the metal of the intake track and it is sealed off otherwise.

I will be more interested in internal photos if you cannot get her to run correctly. I'll watch for updates..

Good Luck!
 
scottmastrocinque said:
Robertx901,

Looking at your extermal pictures, I'm not seeing much to give me pause except the slash cut where the carb mates to the intake manifold. Is that slash open to the atmosphere? If so, it is a source of leakes galore. I presume that it is laying over the metal of the intake track and it is sealed off otherwise.

I will be more interested in internal photos if you cannot get her to run correctly. I'll watch for updates..

Good Luck!
Click to expand...
There should be a plastic bushing in the carb where you see the cut. The cut is there so that the body will clamp down on the bushing/manifold.
 
Thanks John!

I figured there had to be some sealing surface other than metal to metal. I was just checking as I don't have the benefit of before, during, and after photos.

It's that carburetor time of year again in my workshop. :D 7 carb jobs at the moment. Fun, Fun, Fun! :p
 
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