Bert Reganze
Junior member
- Location
- Leiden NL
weird behaviour triple engine
- Thread starter Bert Reganze
- Start date
Laverdalothar
Hero member
- Location
- Germany
Look at the other 2 pump jets, there should be a flat spot at a certain point. the hole in the jet needs to point to the slider/engine and normally, it can only be mounted that way as the seat has a flat spot, too. If there isn't one on the jet, the jet won't fit straight into the hole and won't reach far enough in to jet the fuel into the engine direction, as the hole in the jet will be partly or completely blocked by the seat.
hopefully you also found all O-rings before ultrasonic cleaning... there is one hidden behind a tiny washer... (parts 43 and 50, center left of the pic below):
make sure to replace them and put them back in in the right order (first put the spring over the screw, then the washer and then the O-Ring before you insert everything). The washer keeps the O-Ring safe from getting destroyed by the spring when you turn the screws.
Next after fixing the issue with the acceleration jet, make sure you set the float levels right. it's described in the Dell'Orto book. Best you make yourself a "U"shaped piece of alloy with one side of the U being longer than the other and you adjust the sides in parallel with 18,5mm distance (measured from the shorter, outer side to the longer, inner side). That way you can put the shorter outer side on the sealing surface of the float bowl and the longer side will touch the float. check if the float needle closes at that distance. If it closes earlier, float level is to low. if it does not yet close completely, float level is to high. Adjust the "tong" where the float needle is held with to achieve correct setting.
After that and after all other O-Rings and seals have been properly re-placed, put the carbs on the bike and adjust the sliders. check that they all move equally (if not, your carb set is twisted), open fully and all together. The easiest - even though not the most important position - is to adjust sliders by pulling them completely open until the center hides in the body. Then adjust the other 2 to the same level. Now check if they also are on the same hight when almost closing them for that, screw the central idle adjuster screw in so that the center one opens - say - 6mm (take a drill bit to check f.e.; can be any size around 6 if you don't have 6). adjust the others to the same level (if everything is perfect, they are already on the same level).
Last but not least, adjust the choke sliders to the same level and so that they fully close when the choke lever is closed and fully open all together. this is an important, yet mostly overseen step...!
If you haven't forgotten any washers or seals, this should give you a perfect idle and a good throttle response.
Good luck!
hopefully you also found all O-rings before ultrasonic cleaning... there is one hidden behind a tiny washer... (parts 43 and 50, center left of the pic below):
make sure to replace them and put them back in in the right order (first put the spring over the screw, then the washer and then the O-Ring before you insert everything). The washer keeps the O-Ring safe from getting destroyed by the spring when you turn the screws.
Next after fixing the issue with the acceleration jet, make sure you set the float levels right. it's described in the Dell'Orto book. Best you make yourself a "U"shaped piece of alloy with one side of the U being longer than the other and you adjust the sides in parallel with 18,5mm distance (measured from the shorter, outer side to the longer, inner side). That way you can put the shorter outer side on the sealing surface of the float bowl and the longer side will touch the float. check if the float needle closes at that distance. If it closes earlier, float level is to low. if it does not yet close completely, float level is to high. Adjust the "tong" where the float needle is held with to achieve correct setting.
After that and after all other O-Rings and seals have been properly re-placed, put the carbs on the bike and adjust the sliders. check that they all move equally (if not, your carb set is twisted), open fully and all together. The easiest - even though not the most important position - is to adjust sliders by pulling them completely open until the center hides in the body. Then adjust the other 2 to the same level. Now check if they also are on the same hight when almost closing them for that, screw the central idle adjuster screw in so that the center one opens - say - 6mm (take a drill bit to check f.e.; can be any size around 6 if you don't have 6). adjust the others to the same level (if everything is perfect, they are already on the same level).
Last but not least, adjust the choke sliders to the same level and so that they fully close when the choke lever is closed and fully open all together. this is an important, yet mostly overseen step...!
If you haven't forgotten any washers or seals, this should give you a perfect idle and a good throttle response.
Good luck!
Jo said:
I had bad ignition pickups recently, but the behaviour was very different from what Bert describes. At random moments the engine would cut out immediately. Only to reignite a second later with foot long flames of unburnt fuel banging out of the exhausts. First time round gave me the giggles.
If you are in northern holland, Oebele Herder can help out. If in the south you could also work with oldskoolmechanics in antwerp.
The Sock
Hero member
- Location
- London, England
Mingh said:
Might be worth checking the ignitition switch.
Turn it on, gearbox in neutral, see if you can get the neutral light to flicker by gently wiggling the key.
Take out the key and squirt a little ACF50 in the keyhole, couple of times.
Key back in, switch through all three positions several times and repeat 'Step 1'.
This has kept my original switch in line for 44 years.
Bert Reganze
Junior member
- Location
- Leiden NL
Laverdalothar said:
Lothar, thanks for all the tips and extensive explanation. Will work things out, and hope for a perfect idle and good response. Last but not least, what to do with the mixture screws? 1.5 turns open as a basic setting? One turn is 180 degrees, right?
Don't want to hijack this thread but it was due to the insulation and soldering of the wired on the pickups having become brittle, causing a contact interruption occasionally. Replaced, and after about 100 km's it is safe to say that the funny trick with the fire spitting is gone....
The Sock said:
Bert Reganze
Junior member
- Location
- Leiden NL
Laverdalothar said:Look at the other 2 pump jets, there should be a flat spot at a certain point. the hole in the jet needs to point to the slider/engine and normally, it can only be mounted that way as the seat has a flat spot, too. If there isn't one on the jet, the jet won't fit straight into the hole and won't reach far enough in to jet the fuel into the engine direction, as the hole in the jet will be partly or completely blocked by the seat.
hopefully you also found all O-rings before ultrasonic cleaning... there is one hidden behind a tiny washer... (parts 43 and 50, center left of the pic below):
make sure to replace them and put them back in in the right order (first put the spring over the screw, then the washer and then the O-Ring before you insert everything). The washer keeps the O-Ring safe from getting destroyed by the spring when you turn the screws.
Next after fixing the issue with the acceleration jet, make sure you set the float levels right. it's described in the Dell'Orto book. Best you make yourself a "U"shaped piece of alloy with one side of the U being longer than the other and you adjust the sides in parallel with 18,5mm distance (measured from the shorter, outer side to the longer, inner side). That way you can put the shorter outer side on the sealing surface of the float bowl and the longer side will touch the float. check if the float needle closes at that distance. If it closes earlier, float level is to low. if it does not yet close completely, float level is to high. Adjust the "tong" where the float needle is held with to achieve correct setting.
After that and after all other O-Rings and seals have been properly re-placed, put the carbs on the bike and adjust the sliders. check that they all move equally (if not, your carb set is twisted), open fully and all together. The easiest - even though not the most important position - is to adjust sliders by pulling them completely open until the center hides in the body. Then adjust the other 2 to the same level. Now check if they also are on the same hight when almost closing them for that, screw the central idle adjuster screw in so that the center one opens - say - 6mm (take a drill bit to check f.e.; can be any size around 6 if you don't have 6). adjust the others to the same level (if everything is perfect, they are already on the same level).
Last but not least, adjust the choke sliders to the same level and so that they fully close when the choke lever is closed and fully open all together. this is an important, yet mostly overseen step...!
If you haven't forgotten any washers or seals, this should give you a perfect idle and a good throttle response.
Good luck!
Took a while to find the time. But everything done, but still the same problem.
I had all the time the impression (weird behaviour was always accompanied by high revs at idle!) that the acceleration pumps did not do their job well: There was no fuel visible in all carbs after full throttle. So I bought a few new parts for the acceleration pumps. Still, only after more than 10 times and more full throttle there is fuel injected, but not all carbs together, and still not each time. But the amount of fuel seems a bit too much to mee; how much should it be?
Now I removed the acceleration pump valves, the nr 68, in the float bowl. No problems anymore! So it looks that the problem stems from (one of) the acceleration pumps. Will start by replacing the nr 54. Hopefully this will solve the problem