engine idles great but shudders under load till 2500rpm..

then runs strong. it has some type of electronic ignition and a electric fuel pump.
could this have anything to do with idle jets?

Bob,
When you say it shudders under load...letting out the clutch?
How does it respond while you rev it up with no load? Could be clutch-related if it's fine.
Although, if it's been awhile, you should pull the idle jets and give them a good cleaning.

never thought about the clutch. i will have to do some more driving/testing. feels like the engine shuddering until it hits 2000rpm, could be clutch if the 2387 has too much torque for the clutch disc. its a kennedy stage 2.
will take it out tomorrow and put it thru its paces.

not the clutch, no slippage at all in agressive launches and shifts.
must be the carbs...engine feels like it bogs down and shudders slightly till 2000rpm and then the motor kicks in and its like the afterburners are on.
idles fine and in neutral the engine seems fine but put it under a load and it starts to bog

Accelerator pumps?

Where's Larry when you need him? ;)

Larry is right here, he just got home from a motorhome trip to Chula Vista beach.

Several things could be wrong including carb's, faulty fuel pump, dirty fuel filters, faulty engine or transaxle mounts, clutch, faulty Boden tube and ignition.

Clean out the idle jets, replace fuel filters, remove the distributor and clean the advance mechanism, check the transaxle and engine mounts, make sure that none of the rubber cushions are damaged and, check ALL bolts for torque. It's possible that a rear main seal or a transaxle mainshaft seal has sprung a leak and in many cases, it will cause "shudder" only upon take off from a dead stop. A faulty Boden tube can also cause a similar problem.
Racing up the engine and "popping the clutch" usually won't reveal this problem.

It's VERY difficult to diagones this kind of a problem without being able to drive the car.

The list, as posted above, are the most likely to cause such a problem.

thank you larry, to me it feels like a cylinder isnt firing at lower rpms but hit that sweet spot and it runs like a bat out of hell..could this be coil related?

Bob-

10 bucks says it's idle jets. It's been 2 days. Just check 'em.

Dear Bob,

At least start with cleaning the idle jet. If this cure your problem, then you are done, otherwise follow the steps that Larry informed you to check. Those pesky idle jet usually cause the low rpm to stumble, but clear up on higher rpm (as the idle jet does not control the bigger throttle opening).

Good luck

Eddy

Call Greg!.....
He tuned up my carbs a little over a year ago. Made a great difference.
Ernie

If you notice, the first thing I recommended is to clean out the idle jets. Associated with plugged Idle Jets is popping through the carb's. But, since the car is there and I'm here, it can be difficult to solve a problem that could be one or a combination of problems.

I would first isolate which cylinder is at fault by pulling one plug wire at a time. The rpm's should decrease some. If you come to one wire that does not drop, then you have found the offending cylinder. As Larry mentioned, clean that idle jet (best to do them all) and go from there. ~Alan

All those in favor of cleaning the idle jets say aye...

ok ok ok...i get the hint, damn, feels like i have numerous wives.
will report later. not sure how your 44s sit but my bergmann everything faces the wheel wells. even my stubby driver woulnt fit along with my 3x hands, flashlight and mirror.
so im taking the carbs off to do it right, one side done and working on other....hope my scotch holds out. will keep posted.

You may want to consider cutting access panels in the wheelwells- you'll likely be doing this a lot.

Bob,

Is it a "shudder" or a "stumble" . A shudder, at least to me, is a multiple shake of the entire car, like if someone grabbed both of your shoulders and gave you a couple of shakes. A stumble is like a hesitation or as if you didn't pick up your foot when you were walking a had a little trip.

spent most of afternoon pulling carbs, linkage etc. cleaned the jets and it still runs the same. i will take it to my vw guy greg next week,i have had enough.

Just curious ... How old are your plug wires?
Over time the heat breaks down the insulation creating resistance. You will get a cross fire ( spark jump) amongst the wires creating a miss fire / shutter. Great way to check it is ...at night with the engine running, take a water squirt bottle and lightly spray the ignition wires. It has to be dark to see whats going on. If there is high resistance in your wires ... you will see the spark jump. The fix is replace them. Stay away from the cheap colored wires made it China.
My car is doing the same thing right now . Just waiting for a new set of Taylor 10mm wires. Its a bit over kill. 8mm Bosch wires are good for mildly built motors

joe, where did u order the wires from.

Bob call roland he used the taylor made in the usa wires on my new engine. They do come in colors.

Marty

I believe I mentioned spark plug wires in my email to you however you need to test them before you jump in and start throwing good money at everthing that could be the source of your problem.

You need to know what's wrong and fix that problem rather than doing a shot gun approach.

If wires are your problem, (Taylor made plug wires are good) go to Taylor's web page and look for the Dealer locator link towards the top of their page:
http://www.taylorvertex.com/Products/index.cgi/SparkPlugSets

Barnco....
Count on 'ol ern for a ride home n back in the bug slayer!
After all, MARINES are in the Navy too!

I ordered them from CB Performance . They had the best price. Yes, they do come in colors.

If you're brave and can't wait for night fall ... you can always wet your hand and grab the wires . It only stings for second and you'll get curly hair. The new kid in crew always fell for that one. Boy did they jump!

Of course you checked your carb balance . . . . right???

Note to Bob: We are going to need closure on this thread or we will still be going strong come Christmas. Keep us posted.

close it, im taking a few days off from the car and will let my mechanic look at it.

Bob, Over the weekend I finally intalled the new wires, cleaned out the idle jets and my problem similar to yours is gone.

my mechanic did idle jets, new plugs and #3 wire replaced, runs great now

Bob - I bet it's a relief for you to know it was a relatively simple fix. Now you can get back out there driving those cool roads through the Gold Country!

So I am new to the world of Speedsters, bought my first two weeks ago. I am having the exact same issues with the shuddering until 2500+ rpms on a 1600cc. I have changed plugs, checked and replaced points, checked fuel acc. pump. I think I have a jet clogged also. My question that I hope some one can help with is, does anyone live in Middle TN and have a VW mechanic they would recommend? I can not find anyone listed on the internet within 50 miles of me? Thanks for any and ALL advice!!!

Listed under "shops" tab above right:
https://www.speedsterowners.com/shops/shop.asp?venid=1056

what kind of carbs chip, maybe i can help. bill

Single solex carb 34PICT-3. I am going to replace the fuel filters and mechanical fuel pump. I am not advanced enough to rebuild carbs.
Thanks!

Chip
If all fails I have a almost new carb like the one you have that has been double checked and rebuilt ( by a local engine builder ) just to be sure if you are interested - I went to dual carbs.
Email me for price and details dlschu42 at comcast.net.
Dale

Maybe the shuddering is 'clutch chatter' because of improper Bowden tube adjustment (clutch cable) and not carbureter problems.

you might try an italian tune-up.
big bottle of techron and drive the piss out of it in the upper rpm ranges might cure the missing.

Bob.....
You need help. You are a very sick man.
BTW, are we still going to Morro?

Chip go with an electric fuel pump see thread Dies under Load forlink provided by Larry J. fixed my problem. Don't forget to get a cover for the mech pump.