750 Paso Technical FAQ Digest

discussions specific to the 750 Paso

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Re: 750 Paso Technical FAQ Digest

Post by jcslocum »

Rear Wheel Removal

Rear wheel removal steps here: http://forums.ducatipaso.org/viewtopic.php?f=1&t=3279
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Re: 750 Paso Technical FAQ Digest

Post by paso750 »

16" tires

the original Michelin tires in the sizes 130/60ZR16 and 160/60ZR16 are not available anymore.

The production of the Pirelli MP7 was stopped in the early 90s, the production of the Michelin A59X and M59X was stopped in 2005 after only being produced in batches once or twice a year the years before.
If "new" ones are sold somewhere be aware that these are a minimum of 12 years old, probably older ! Check the DOT number (see below)

Beginning mid 2012 Golden Tyre produced the GT 070 (130/60 ZR16) and the GT 071 (160/60 ZR16). Golden Tyre dismissed the GT 070 and GT 071 in 2016. Shinko now manufacturers the correct sizes. (which have almost the identical thread pattern as the GTs. Golden tyre was a distribution channel used by Shinko.) The Shinko front tire is model SR880 and the rear SR881. (below on the right)


Image Image
In 1998 the Shinko Group purchased the motorcycle tire technology and molds from Yokohama Rubber Co., and began production of these products under the Shinko Tire brand. With manufacturing based in South Korea and design based in Japan, the company has seamlessly combined Japanese engineering and design principles with South Korean production and quality control standards. Today Shinko Tires produces approximately 200,000 motorcycle tires per month.
Other alternatives:

front:
130/70-16, common size produced by several manufacturers as used ie on Honda Fireblade. The bigger tire diameter requires lifting the front fender

rear:
150/80-16, tire manufacturers do not recommend this tire with a 5" wide rim. However in 2009 Ducati Germany issued an official approval for this size ( http://www.ducati.de/service/reifenfreigabe_paso.php ). The tire is very high so it touches the swingarm in the front. Hence you have to adjust the chain excenter as much to the back as possible and/or modify the swingarm. The remaining possibility of adjusting chain tension will be small. Longer side and center stand may be required.

180/60-16, a size produced mainly for heavy toures like Honda Goldwing and therefore not optimal for the Paso but there are exceptions for custom applications like ie the Avon Cobra AV72. Tire diameter is smaller than the 150/80 but it is wider so it`s required to offset the chain (front & rear sprocket) so it won`t touch the tire. (before the AV72, there was the AM42 and before that the AM23)

Tire manufacturers generally recommend to combine only tires with matching characteristics, meaning one should not combine a "slow/flat profile" touring tire with a with a "fast/responsive" Supersport front tire with a sharp profile. I.e. the Avon AV72 should only be combined with a AV45 front.

Not recommended are: 120/80-16, 150/70-16 or 160/70-16 (the only tire this size is out of production anyway)
170/70-16 was not done yet, but it`s very likely you`ll end up with both clearance issues of 150/80 and 180/60 as the 170/70 has the same diameter as the 150/80 and almost the same width as the 180/60-16.

Star twin Motors in the Netherlands ( http://www.startwin.com/ ) meanwhile makes an adapter to lengthen the swingarm and give more clearance for a higher 150/80-16. (Note the tire is already higher and the adapters make the rear come up even more which will change the bikes geometry). My personal guess is that you`ll also need a longer chain. Probably with 108 links like the one of the 907ie. (maybe even longer if you go for a bigger sprocket too to compensate the the effect of the taller tire)
Image

Tire production dates:

on the flank of the tire there`s the DOT number. Until the year 2000 it had 3 digits, after that 4.
The first 2 digits indicate the calender week, the last the production year.
So ie DOT 2306 means production in cw23 2006.

To differentiate the production years with 3 digit codes symbols were added to the number.
DOT 276 would indicate a production in cw27 of 1986 while for a 1996 production year there would be a triangle behind the 3 digit code as can be seen here:

Image

Tire markings

i.e. 150/80B16 71V
80 is the height of the tire as percentage of its width. Hence if the tire is 150mm wide the height is 120mm. 71 is the weight index. 71 corresponds to 345kg max. load (with correctly set tire pressure. Lower tire pressure will reduce max load. At speeds above speed index of the tire max load will decrease). B stands for bias belted, R would mean radial.

The Pirelli MP7, the tires the first Pasos came on:
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Cam Timing

Post by jcslocum »

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Re: 750 Paso Technical FAQ Digest

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Re: 750 Paso Technical FAQ Digest

Post by paso750 »

Side stand modification

if you don`t want it to retract automatically when you lift the bike
Image

or just cut down the head of the side stand bolt so the plate can pass above it

Note, even if sometimes it can selfretract if you`re not standing right and the bike can tip over worse can happen if you modify it and forget to pull it up when taking off.
http://forums.ducatipaso.org/viewtopic. ... 070#p39070
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Re: 750 Paso Technical FAQ Digest

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Re: 750 Paso Technical FAQ Digest

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Re: 750 Paso Technical FAQ Digest

Post by paso750 »

Engine won`t start - what to check

https://app.box.com/s/x8fmn1brzuya97x8z44z

This does not cover the 907ie as it has additional relays and sensors that can cause problems.

If it is an electrical problem do also open the metal strain relief below the ignition switch as sometimes it can cut into a wire.
Image

If the engine stops during a ride and doesn´t fire up again or only after a while there can be additional reasons:
- fuel breather line clogged (underpressure builds up in the tank and the fuel pump won`t be able to deliver enough fuel to the carb. If you hear a "pfff" if you open the filler cap or if it the fires up again with cap removed that might be the case.)
- dirt in fuel line, filter or pump causing clogging as soon as the fuel pump starts building up pressure.
- old ignition coils can run fine when cold but start failing when they get hot. Same for spark plug wires.
- if you recently had the tank removed make sure the tank breather hose and fuel overflow weren`t switched

Bad or high idling of a warm engine can be caused by leak air. I.e. the carb rubber boots of the inlet manifold may start to leak when they become hot. One can use starting aid or carb cleaner spray to detect a leak. If the engine revvs up if you spray on a certain spot you`ve found the leak.

P750 engine running on one cylinder (occasionally)

The problem could be everything from
low voltage to coils and CDI units (due to contact problems in the kill switch)
pick-ups (quite rare)
incorrect pick-up clearance to flywheel (air gap)
pick up wiring (can break where it goes through the engine cover. The pick-ups will measure the correct resistance if a wire isn`t completely broken which makes it tricky)
ground connection to CDI units
CDI units (quite rare)
wiring to the coils (kill switch, ignition switch)
check continuity of all wires that connect coils to CDI units
coils
spark plug (HT) wires
spark plugs, incorrect electrode gap
carb synchronization

HT wires can age and if a coil has cracks in the housing it can be affected by temperature or humidity.
The most common problem though is the wiring with bad connections and old wires with copper rust.
Measure the voltage at the coils and CDI units (orange wire) and if it isn`t nearly the same as the battery voltage clean the kill switch and all electrical connections (specially the main ground connections) then do the wiring mod.
https://app.box.com/s/waxvk1l9g47phfybd6n9
One indicator of low voltage at the coils is if the dropped out cylinders kicks in when rpms are increased. It seems that if there`s a voltage issue it`s most often the rear cylinder that drops out.
Electrical resistance of bad connections does increase with heat btw.

To rule out parts like CDI units or coils swap them from one cylinder to the other (one part at a time) then see if the problem shifts to the other cylinder. If the problem remains the same the parts swapped are ok and the problem is somewhere else. Begin with the spark plugs and work your way backwards to the coils and CDIs.

If the issue remains check compression and valve clearances.
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Re: 750 Paso Technical FAQ Digest

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Re: 750 Paso Technical FAQ Digest

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Re: 750 Paso Technical FAQ Digest

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Re: 750 Paso Technical FAQ Digest

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Re: 750 Paso Technical FAQ Digest

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Re: 750 Paso Technical FAQ Digest

Post by paso750 »

service bulletin gear selector mechanism - all Ducati

https://app.box.com/s/ccqi4o1hoelpn458dffawwf51kiq20cs
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Re: 750 Paso Technical FAQ Digest

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