To gap the valves or not gap the valves?

discussions specific to the 750 Paso

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nazman
Posts: 4
Joined: Mon Jul 31, 2017 9:46 pm
model: 750 Paso
year: 1990
Location: UK

To gap the valves or not gap the valves?

Post by nazman »

Hello all,
I recently done up my old Paso 750. New cam belts, cleaned seized clutch, overhaul to brake calipers. etc. She was sat for 8 years. Question is can I get away with not gaping the valves? Would this cause serious damage to the engine? Or would it simply make the bike ride a little slower? I already ride like an old granny. So a slow bike would make no difference. Local garage is asking for about £300 max to gap the valves. Am on a budget. :( She's got 23000 on the clock. 3000 of those from me (8 years ago). With no problems.

Any advice would be appreciated.
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paso750
paso grand pooh-bah
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Joined: Sun Jul 18, 2004 12:00 am
model: 750 Paso
year: 1987
Location: southern Germany

Re: To gap the valves or not gap the valves?

Post by paso750 »

Question is can I get away with not gaping the valves? Would this cause serious damage to the engine?
The answers are no and it's possible although one could reply 'it depends' to both (I wouldn't).

Incorrect valve clearance can cause burnt valves, ruin valve seats due to excessive heat, wear parts or create other kind of engine damage. How high the risk is depends on how off the valve clearances are and you will only know that if you have that measured. A possible damage could cost you more.
I don't know if GBP300 is a normal price for the job but maybe there are other shops that can do it for less. Also you could check here or on other Duc forums if there's someone in the area who could help out.

Edit: during the 3K mls you rode the bike did you ever have the valve clearances checked? WSM says every 1.800mls. (on the later Supersports it was changed to 3K)
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Derek
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model: 907 I.E.
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Re: To gap the valves or not gap the valves?

Post by Derek »

As above. If you are not up to doing the shims yourself you could at least measure the clearances yourself. It is not difficult.
Then you would be in position to decide whether they are ok or if it needs work done to adjust the clearances. You could even learn to do it yourself :)
1994 907ie
2017 Supersport 939
2015 Scrambler Classic
1982 Pantah 500SL (now sold)


Scotland
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ducinthebay
paso grand pooh-bah
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Joined: Sat Sep 03, 2005 12:00 am
model: 750 Sport
year: 1990
Location: SF Bay Area

Re: To gap the valves or not gap the valves?

Post by ducinthebay »

Most shops will charge you a lot less if you take all the body work off yourself before taking it to the shop. Tell them that when you call for a quote.

Phil
Duc in the Bay
1990 750 Sport x2-Rosso Blanko (900ss copy) & Nuovo Nudo (Scrambler project)
1991 907 -mostly stock
2002 ST4s - Lots of mods.
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paso750
paso grand pooh-bah
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Joined: Sun Jul 18, 2004 12:00 am
model: 750 Paso
year: 1987
Location: southern Germany

Re: To gap the valves or not gap the valves?

Post by paso750 »

very good point. :thumbup:
If you do that (cable)tie the upper oilhose to the horizontal frame bar and remove the rubber blocks on top and bottom of the oil coolers and the two round rubber plugs that you'll find left and right on the headlight frame. You could lose those when riding w/o the fairing.
nazman
Posts: 4
Joined: Mon Jul 31, 2017 9:46 pm
model: 750 Paso
year: 1990
Location: UK

Re: To gap the valves or not gap the valves?

Post by nazman »

Thanks all. Particularly PooBar and Derek. Great suggestions. Will be removing the tank because its rusted. that'll give access to the cam covers. Will remove and check the clearance. Hopefully all is fine. Otherwise, she's off to get gaped.

Thanks again guys. The 'old granny' should be roadworthy before next season.
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