Dellorto jetting?

[Junkers]

Hey there

I have just bought myself a genuine Dellorto 19mm PHBG carb and fitted it to my air cooled bike. It idles beautifully but when you try and rev it, it will chug smoke and surge until you have held the throttle back long enough and the revs have picked up... then shes as good as gold.

Just wondering if anyone knows what Jets suit the air cooled motors or whether anyone knows where to get jets from? It's currently jetted for a husqvarna 50cc motor.

Cheers

[mossy1200]

Hey there

I have just bought myself a genuine Dellorto 19mm PHBG carb and fitted it to my air cooled bike. It idles beautifully but when you try and rev it, it will chug smoke and surge until you have held the throttle back long enough and the revs have picked up... then shes as good as gold.

Just wondering if anyone knows what Jets suit the air cooled motors or whether anyone knows where to get jets from? It's currently jetted for a husqvarna 50cc motor.

Cheers
Tuning it will involve getting the top end correct first then working your way back down to the low revs.
top end with main jet,crossover from mid to top end with needle then mixture screw for the idle.ignore the midrange until you have top end then adjust needle.

Sounds like its way to rich.

[DELLORTO]

DELLORTO's my name.....:sunny:

try sourcing some jets from a husky dealer, even better, what jets does it hav in it?? ive got some spare ones

[Junkers]

It's the throttle response that is suffering, especially when blipping the throttle. So you think the needle is mainly responsible? Once it's rolling at WOT it pulls like a school boy but I think it could be better. What difference does a flat/wide head needle make compared to a sharp/narrow head needle?

Dellorto - I'll open it up tomorrow and have a nosey, it should just have the number stamped on the face of the main jet right? It is setup for a husky 303s motor whatever that is, I couldn't find anything on it.

[imdying]

What difference does a flat/wide head needle make compared to a sharp/narrow head needle?Have a guess :) What do you think it would do?

Phil has one of these for his B1, with a range of jets IIRC.

Give us a yell if you want to come out for a bash on the weekend.

If it's a genuine jet, it'll have a number stamped on it.

[Junkers]

Just popped the float bowl off before, it's running an '86' jet. I got my friend to take it for a spin down the road to see how much smoke it was blowing at WOT, turns out to be a trail about a ft long. Is it meant to blow smoke under load at speed?

Thought as much. I have another needle here out of a china rep carb, may give that a go. Didn't get to see much of him riding it around as a cop pulled over and told us to get off the road. :shifty:

Where do you guys meet up? I am only new to riding these, I've seen the track days they hold at the go kart track on moorhouse ave. Looks like fun.

[imdying]

Just popped the float bowl off before, it's running an '86' jet. I got my friend to take it for a spin down the road to see how much smoke it was blowing at WOT, turns out to be a trail about a ft long. Is it meant to blow smoke under load at speed?Have a look at the videos that Mohawk posts, those show the typical smoke output... shouldn't bee too much though, but should be visible... two strokes are only in trouble when they stop smoking hahahaha. I *think* Phil might have a 70 or 80 in his box, I'll try to remember to ask him on Friday.

What fuel/oil ration are you running?


Thought as much. I have another needle here out of a china rep carb, may give that a go.Definitely give it a go, might be just the trick :)


Where do you guys meet up? I am only new to riding these, I've seen the track days they hold at the go kart track on moorhouse ave. Looks like fun.We meet up out Hornby, pm or rep me with your number and I'll give you a ring on Saturday or Sunday morning. We're still pretty green, but having a good time learning :)

[imdying]

Do you have a picture of the bike? A 19mm PHBG is a pretty big carb for an aircooled bike... is it a Daytona, or something quite a bit 'hotter'?

[Junkers]

I'm currently running 25:1, it's just on a standard 'cag' (I think it's called that?) Just one of the millions of trademe pocket bikes floating around. I bought a 19mm dellorto as hkmotos who mainly do most of the aircooled components sell them as a kit so I thought that would be the go.

I'm keen for a bit of riding but work Saturdays and my mode of transport is in pieces all across our garage floor. Where do you guys take them out to in hornby? Didn't know there was a track out there.

I'm pretty sure I have met you before, I work at repco burnside. I think you may have brought your RGV in once. Had a chat to you about it, was that you?

[imdying]

I'm currently running 25:1, it's just on a standard 'cag' (I think it's called that?) Just one of the millions of trademe pocket bikes floating around. I bought a 19mm dellorto as hkmotos who mainly do most of the aircooled components sell them as a kit so I thought that would be the go.

I'm keen for a bit of riding but work Saturdays and my mode of transport is in pieces all across our garage floor. Where do you guys take them out to in hornby? Didn't know there was a track out there.

I'm pretty sure I have met you before, I work at repco burnside. I think you may have brought your RGV in once. Had a chat to you about it, was that you?Yup, not too many Lucky Strike RGVs about in this city (sadly). There's no track in Hornby, but there's a suitable car park that the owner lets us use out of hours if we look after it :) Sunday it is then! Do you need a lift?

I would have thought a 19mm dellorto (or is it a replica, did it cost over a $100?) would've been too large for the A115 engine... that's the same carb as the ZPF has! What came in the kit?

Had a read back over your old posts, you've had a bit of trouble with it? Most things can be sorted :yes: The plugs cap and leads are problematic on those motors, the cap is ahhhhh, dodgy at best? :laugh: Get yourself a metre of HT lead from work (any of that copper multistrand stuff is fine), and either a plug cap or a pre made lead that we can steal the cap from... that'll eliminate one problem.

[Junkers]

Yeah it definitely is at the big end of the scale, gives me leg room to work the motor though. It's a genuine carb, I ordered it from the UK. To be honest it was worth the money after I have spent so much on cheap carbs that constantly leak and don't run well. I think I have been through 5 carbs including a dellorto rep.

Yeah man, I'm keen for a spin on Sunday, what time were you thinking? I'd be stoked as if you could pick me up. Flick me a txt on 021 156 3194.

Btw can you use silicone leads?

[Gadgit]

19mm del might be a bit huge for the standed engine... but I ran one on a moddified daytona engine. It needed a 0.96 jet so as not to pop holes in pistons and also needed to run a adjustable clutch because below 4000rmp there was nothing but it would scream at the top. Brett runs a 19mm on his mod also and is getting alot more power then the one I did and his top end must be somewhere round 14000rpm .. not bad concidering the standed engine is only good for 9-10000rmp.

[imdying]

It's a genuine carb, I ordered it from the UK. To be honest it was worth the money after I have spent so much on cheap carbs that constantly leak and don't run well. I think I have been through 5 carbs including a dellorto rep.Yeah, know what that's like... I have a video of me tapping my replica with a spanner last weekend when the up till then reliable needle and seat decided to leak :blink: Phil has genuine PHBG on his with a clear float bowl, it's definitely better made.


Yeah man, I'm keen for a spin on Sunday, what time were you thinking? I'd be stoked as if you could pick me up. Flick me a txt on 021 156 3194.About 1:30ish.


Btw can you use silicone leads?You probably could, but a copper core has been easy to work with.


also needed to run a adjustable clutch because below 4000rmp there was nothing but it would scream at the top.Much point running an adjustable clutch on a standard?

[Gadgit]

Much point running an adjustable clutch on a standard?


Yea an adjustable clutch helps us heavys off the line better and better out of hair pins fi your light (less then 55kg ) I wouldn't bother tho

[imdying]

Heh, we're all heavier than that... nobody double though :shutup:

[newmanz]

Hey there

I have just bought myself a genuine Dellorto 19mm PHBG carb and fitted it to my air cooled bike. It idles beautifully but when you try and rev it, it will chug smoke and surge until you have held the throttle back long enough and the revs have picked up... then shes as good as gold.

Just wondering if anyone knows what Jets suit the air cooled motors or whether anyone knows where to get jets from? It's currently jetted for a husqvarna 50cc motor.

Cheers

49cc 2 stroke air cooled (using an S bend HP pipe) and the E2 type (dellorto copy carb) runs best with the .75 # jet ....... tried the .80 # jet first and was bogging down low end too much and hauled arse top end... but the .75# jet gave a very good balanced power delivery

[imdying]

49cc 2 stroke air cooled (using an S bend HP pipe) and the E2 type (dellorto copy carb) runs best with the .75 # jet ....... tried the .80 # jet first and was bogging down low end too much and hauled arse top end... but the .75# jet gave a very good balanced power deliveryHave you ever built an A115 that could use a 19mm carb successfully? Could you build more of them?

[newmanz]

Have you ever built an A115 that could use a 19mm carb successfully? Could you build more of them?

You can easily do it yourself.
Heres the basic setup we have been using:

A115 49cc 2 stroke or similar (air cooled)
S bend HP pipe
E2 HP carburetor ( dellorto 19mm copy )
E2 Jet kit (comes with various jet sizes)
We found on the track the .75 number jet worked best.

Can also use a 1/4 turn throttle controller ( just get or make a slightly longer cable)

If you want serious power then go the pre made A115 GP engine, that thing is flippin crazy power for an air cooled, new ones coming have a new port design for even more power than before. :scooter:

[imdying]

If you want serious power then go the pre made A115 GP engine, that thing is flippin crazy power for an air cooled, new ones coming have a new port design for even more power than before. :scooter:Been considering this for when we've sorted out the water cooled bikes 100%. Could build our own, but if we each buy one of these, then at least our bikes will remain on a level playing fields (rather than one of us doing the cheque book racing thing heh). Cheers :yes: