new guy

[Magman]

Hello, my name is Steve. I live in St. Louis, Missouri USA.
I have a 1969 350 Desmo that is running good except for some carb problem. Under a load the engine runs smooth. When running not under a load the bike is jerky. I managed to break the main jet:/ I need to find a new one. The bike is all stock USA Sebring. It has an 29mm SSI. I pulled the 29 mm VBH carb off my 1970 450 Desmo and broke the choke jet now I need that part. The bike ran smooth and idled great but after a mile down the neighborhood it quit running. It starts but dies a few times then won't start. Any ideas please chime in.

[Jordan]

Welcome.
Please send photos of the broken jets.

[Magman]

Can we post photo's here? A photo of a similar unbroken jet or of the broken jet for each the carb?

thanks
magman

[JimF]

Welcome!

You can add pictures to your posts.

There is a tab at the bottom that says "Upload attachment."

By the way, a SSI29 sells from $400 to $800 (opening bid) on eBay.

Jim

[Magman]

I am attaching a photo showing the broken main jet for my Delorto SSI29D. Its 120 mm

I have found this jet and also the choke jet for my other Delorto carb from Guzzino.com. I do not know about ordering things on the internet across the pond. I have recently had Identity theft and a little paranoid. Can anyone tell me if this is a reliable source or of a source here in the USA for Delorto parts?

thanks
Magman

[Nick]

If you plan on riding the bike regularly, the best thing you can do for it is ditch that stock carb and put a 28mm Mikuni (round slide) on there. The bike will start easily, idle well and put out a couple more HP. Parts are also easily sourced. My 350 was transformed by the change. You can make an adapter with pvc that slides over the stock manifold but has the same OD as the Mikuni, then mount with radiator hose and clamps. The longer intake tract which results from this setup also gives the engine more punch.

She don't look like much but she runs strong and is as reliable as a hammer:

[Magman]

thanks Nick.

My 350 was my fathers favorite bike. He threw a chain 40 years ago with 6,000 miles on the bike and it sat in the garage until he passed away in 2000 and I have stored it for the past 13 years. I have it running now. The plan is to see if it will run for a few hundred miles and worth restoring. I have ridden it 5 miles to work at 35-50 mph half dozen times now. I really like riding the bike except for adjusting to the non-standard controls. The only hang up right now is the carb. It starts good but wont idle and surges and jerks riding down the road unloaded. It runs great under power. I need to find some tires. I am riding on the original Pirelli's(sp). I might try the Mikuni if the Delorto's are too finicky for daily use and get the bike running reliably. I am looking forward to riding this bike. I did put a Levis pant Leg on this fiberglass seat pan and stuff it with some foam...Its working for now.


Magman

[JimF]

I have ordered from Road and Race (Australia), and several places in the UK without incident. I never hesitate, and I don't think you can given that parts sellers are sparse.

BevelHeaven carries some singles stuff and they are US based.

Syds Cycles in Florida probably has more singles stuff and Malcolme there is extremely knowledgeable, but I think you have to phone in your order there.


I have a SSI29 on a 250 and a Mikuni 26 on another 250 and the Mikuni makes the bike run like a clock whereas the Del'Orto is finicky. The Del'Orto is effective but crude. It's hard to start and impossible to idle if I try to filter the incoming air. The Mikuni makes the bike esier to start, easier to idle. Yes it's a sin to put a Japanese carb on, but the bike came to me that way which squarely puts the sin on the previous owner's shoulders.


It has the scrambler air filter on it and that says "Del'Orto' so most people don't notice.


By the way, that twin filler tank is kind of worth a TON of money.



Jim

[double diamond]

Guzzino is Paul Montgomery, stand up guy and great to deal with. You should have no reservations ordering from him. Based in Los Ageles area. Herdan also has some Dellorto parts but thin on the SSI parts. There are afew ebay sellers: bsanut (eurotrashjamabalaya Joe Carter), genuinenos, guzzino occasionally lists on ebay, but most ebay sellers are pretty expensive. Dellorto.UK seems to have everything you could want but they're in the UK. Might try motoitalia as well, Aermacchi source but Aermacchi used similar Dellortos as Ducati. Make sure the air adjustment circuit (often confused with a starting circuit since the handlebar lever looks like a choke lever) is working properly. Also, the slides on SSI carbs are usually worn out and often the needle/needle jet, which could lead to the problems you're having.

[DucRedux]

Another source to try is MG Cycle. They handle Dellorto components and were very helpful in getting miscellaneous components for my rebuilds.