Welcome to the forum ,stunning work, looks beautiful ,look forward to reading that you have it running
Actually 40mm Dellortos do come with chokes, some have ticklers.like on my 76 860 and your Hailwood, my '82 Hailwood has a dash operated dual choke lever cables and then my F1 has carb choke levers on the top of each carb. Always starts on the choke easy especially after i rebuilt the carbs.
Hi all If this has the two Bosch ignition amps like a similar year Darmah .... if not so sorry my post is NA .... Check the plugs on the ignition amps ...... I removed mine once to silicone grease them ..... then had all sorts of trouble after ...... what I did not notice is several pins pushed slightly back out of the plug as I re inserted it therefore intermittent/ non connection. The little tangs on the pins crimped onto the wires were not engaging into the plug body. Just think as he's had it in bits...... Gerr
Pete 1950 has pretty much said it all. I might add that the accelerator pumps can be primed by removing the brass screw in the top and dribbling some fuel in while working the slide at the same time till the pump is running OK. 98SPS also mentioned checking that there is a good earth from the engine to battery -ve. Thats very important. Great bike though except perhaps for the blue springs!! I have a production racer version from 77 and with HC pistons and Imola cams. Its a bitch to start but once running..........!
Yes, removing the accelerator pump screw works to prime, i removed mine and held my finger over the hole to form a vacuum while twisting the throttle, 3 or 4 twists later and i had it primed and squirting, then just put the screw back on. Settings for the accelerator pump screw are not really critical, supposed to be 8cc per 20 twists, but its only an accelerator pump.
Thanks Gerr, I will look at the connections again. And thanks to everyone else for your suggestions. I have tried them all with still no success. The blue shock springs were not my idea (owners) they are air shocks purchased when the bike was new. I talked to Steve at BH yesterday. He suggested everything except priming the accelerator pump and suggested purchasing his $12.95 Dellorto Sync and tuning instructions which I did. I did learn about the priming from that. I am going to call John Foyston here in Portland, and pick his brain. He had the Ducati dealership here in Portland where the bike was purchased in 1978. Sorry, not at liberty to name the owner. Cheers, George www.gekrestorations.com
Update! OK, I got it started today. Not sure how but I think some starting advice from John did it (a little throttle on startup). It is not running on one cylinder at idle. I have swapped all the electrics from left to right and it still is not firing on the front cylinder so that narrows it down to the idle circuit of the front carburetor. I have dropped the bowl, cleaned the idle jet and still not correct. Tomorrow I will pull the front carb apart and check everything. I did remove the pilot adjuster screw, pilot jet, and squirted carb cleaner and 100lbs air through and everything to clean but still not working properly.
I did have a case once on a black and gold 900ss where the carbs would not seal on the inlet manifold correctly. It is essential to have no additional air coming in at idle in particular.
OK, it may be helpful to go into more detail. The DellOrto PHM 40 carbs fitted as standard to 750SS greenframes, 900SS, and 900 Hailwood models in the 1970s do not have chokes fitted, just ticklers. The carb body castings have provision for a choke assembly on the side, and it would be possible to attach a choke body (part 8887) with three screws - some machining would be needed. This is what the choke housing looks like: https://www.dellorto.co.uk/shop/del...arburettor-parts/phm-parts/phm-choke-housing/ The choke, if fitted, can be operated by a lever on the carb body like this: https://www.dellorto.co.uk/shop/del...tor-parts/phm-parts/phm-lever-choke-assembly/ ... or via a cable leading to a remote lever like this: https://www.dellorto.co.uk/shop/dellorto-motorcycle-carburettors-parts/carburettor-parts/phm-parts/cable-choke-kit-3/ Most of these parts are the same as PHF 36 parts. Some later 900 bevels had chokes fitted to the carbs, as you rightly say @Murph . Some bikes were fitted with the "smoothbore" version of the PHM 40 carbs, where the casting has no provision for chokes. Since the originator of this thread apparently does not have chokes on his carbs, all this is academic. I was trying to offer advice as to how to obtain enough, but not too much, enrichment for kickstarting from cold.
True, but that's a lot of trouble to go to. The accelerator pumps should be self-priming. The diaphragms are quite delicate, and if they are 40 years old they'll probably be perished or holed. Replacing them is a good idea https://www.dellorto.co.uk/shop/dellorto-motorcycle-carburettors-parts/carburettor-parts/phm-parts/phm-phf-pump-diaphragm/
Understood Pete, I never was a fan of ticklers so when I punched out my 860 gt to a 900 I enlarged the intakes to 40mm and promptly put a set of 40's with lever chokes on it.
OK, back on subject :^). Please see my update below. I now have it running but only on one cylinder at idle. I have cleaned the idle circuit (as described below) without success. Any ideas why the idle circuit is not working? I am about to pull the carb and go through everything again but it would be nice to look for something specific. Thanks, Update! OK, I got it started today. Not sure how but I think some starting advice from John did it (a little throttle on startup). It is not running on one cylinder at idle. I have swapped all the electrics from left to right and it still is not firing on the front cylinder so that narrows it down to the idle circuit of the front carburetor. I have dropped the bowl, cleaned the idle jet and still not correct. Tomorrow I will pull the front carb apart and check everything. I did remove the pilot adjuster screw, pilot jet, and squirted carb cleaner and 100lbs air through and everything to clean but still not working properly. #31
Armchairducati: I'd swap carbs and see what happens; if the problem follows the carb then you are probably right about the front carb idle screw. I'd simply leave the slides connected to their cables and just swap the carb bodies over. Obviously the adjustment screws will be on the wrong side, only an issue for the rear carb as the battery will be in the way so I'd screw the idle screw on that carb all the way in then back out 2 turns. This is only a test. You probably did this already. If the problem remains with the front cylinder then there are a number of possibilities; a spark at the plug outside the head doesn't necessarily mean a good strong spark under compression with the plug in the head. You mentioned that you swapped ignition components over but which ones? You also mentioned electronic ignition. Do you mean the original Bosch system or a newer electronic ignition? If original Bosch, I've never tried, but on my bike, I don't think the original front HT lead was long enough to reach the rear head and these leads are epoxied into the ND coils. I don't think it would have been easy to swap the HT leads and coils. If you just swapped Bosch units over, and still saw outside-the-head sparks, it's possible that you have a bad front ND coil. My old MHR suffered from this; all looked OK and tested fine until plugs were in and the bike was started then the front head was intermittent. I installed a new Sachse system, new Dynatek 5k coils, new HT leads and caps and a Shendingen regulator. I'm north of you, close to Vancouver, BC. Call me any time if you'd like to talk about this. Rick 604 315 1819
For what it is worth, this is how I set-up and started my 81 MHR last year after a 29 year rest. Following a very thorough going-over that included lots of electrical check-outs and carb rebuilds, I set both carb idle screws 2 turns out from all the way in. The throttle stop screws were all the way out so that they were only just touching the slides, with the throttle cables adjusted to lift simultaneously, gauged by sticking a finger in the rear carb and looking inside the front while twisting the throttle. My carbs have ticklers; I turn on the petcocks then depress each tickler while counting to 6 (at 7 they pee gas). I twist the throttle twice, wind the kick start to compression, turn the ignition on and give the kick start a good kick then catch the motor with a little throttle and hold it at around 1800-2000rpm and give it a good 5 minutes to warm up. During the warm up, I tweak the throttle stops small, equal amounts in to lift the slides so that the bike will idle by itself at around 1800rpm. Ideally, I'd have ridden the bike around the block a few times but it wasn't insured so I just annoyed the neighbours. I then shut the motor down, attached my MotionPro vac gauges, restarted the bike and adjusted the throttle stops to equal vacuum at 1500rpm and then tweaked the throttle stops to get the strongest idle rpm on each cylinder. I repeated this down to 1000rpm.
Trying to keep this in bite-sized chunks. I swapped my slides over; after years of use, the sloped contact strip of the slide that is touched by the throttle stop screw gets indented by the slide dropping down on the screw. Swapping the slides over exposes virgin contact area for slide height adjustment. I also found that simply removing and replacing the rubber cable cover on top of each carb was enough to slightly straighten the cable path and tug a little on the slide so push them all the way down when making the vac gauge adjustments. Make sure there's at least an equal 2mm play at the throttle and that turning the bars left and right doesn't compromise the throttle play.
A few comments before going to bed: There's been discussion about accelerator pumps, just pull the air filters off, twist the grip and look down the chokes; if there's a squirt of gas then all is OK. The throttle cable routing shown in one of the photographs looks wrong and too tight to me; my cables stick straight out from under the tank on the inside of the right upper fork leg and turn around in a longer sweep to the throttle. Mine pass under the lever but if my cables were longer, I'd have adjusted them to go over the lever so that the cable path would go straight out from the throttle and around under the tank rather than pointing down a little first. Most bikes I've seen are the same as mine.
