Newbie jetting questions

SFJOTA said:
Hello Paul,

I do believe that Green Bible and Laverdamania’s standard settings are identical.

Gijs van Dijk renewed my carbs, i could check the receipts. However, i found these ‘standard’ settings to be too rich, so i simply lowered the needles to the highest slots. A bit of work mind you, not a easy as with my SF by far. 🥴

Haven’t had the time to ride the bike yet, mainly due to winter and road salt. So can’t judge any results yet.

However, my SF’s rideability bettered quite a bit

Jilles
Click to expand...

Hello Jilles
if Gijs did recondition your carbs, what is the reason you found them too rich?
I'd go back and ask Gijs for his reasoning first ...

Cheers
Jo
 
Hello dear Jo,

Dreadfully sorry for my late reply.

Reason for finding the mixture too rich; blackened plugs within 200kms, reluctancy to rev, blown plug due to soot/mixture and an awful power delivery.

I use 98 octane Ethanol-free gasoline. That does not seem to be the issue.

FYI; I found the same issues with my Triton, SF and now JOTA.

True; I have not tested yet, so i cannot remark on the effect of lowering the needles.

Still an interesting matter, as i have read similar findings in these pages...

Best regardsfrom Holland, Jilles.
 
I built some 4 garages but as life goes on you loose work place = Mostly Women issues and raising Children.

Wanna to tune your bike - Like dissembling and cleaning the carbs = Can't find your tools and don't have a work area.

That's about "IT" for being a Motorcyclist - It's a Curse ;o)
 
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Double garage, Jo;

JOTA bettered quite a bit lowering the needles to top slot. All of the earlier items addressed bettered quite a bit. I have not checked plug colour yet.

Did it solve all the issues? No, it hasn’t. I’m still convinced power should be better. But the effect was quite dramatic and i am convinced i went in the right direction.

The bike still is on it’s original ignition, which i suspect isn’t as it should be anymore. However, the bike is bog stock and i am reluctant to switch to Sachse, as that would be the first part non-original for this bike, bought 2 years ago from it’s first owner... 🥴

Choices, choices... B.R., Jilles.
 
SFJOTA said:
Double garage, Jo;

JOTA bettered quite a bit lowering the needles to top slot. All of the earlier items addressed bettered quite a bit. I have not checked plug colour yet.

Did it solve all the issues? No, it hasn’t. I’m still convinced power should be better. But the effect was quite dramatic and i am convinced i went in the right direction.

The bike still is on it’s original ignition, which i suspect isn’t as it should be anymore. However, the bike is bog stock and i am reluctant to switch to Sachse, as that would be the first part non-original for this bike, bought 2 years ago from it’s first owner... 🥴

Choices, choices... B.R., Jilles.
Click to expand...
If you insist on keeping it original then you have to live with what it is - even though 95% of members on this forum who own a triple know that a well sorted elec system (like Ignitech and Sachse) will deliver vast improvements - by all means keep the std stuff on a shelf somewhere so you can reconvert it. But for my money, rivet counting can sometimes end up costing you money - and a lot of time! Sorry, just my two lire worth.
 
Thanks for the info and suggestions above - I haven't been able to start the bike to try anything for a month because I've been sorting out the chassis - had to change every single bearing outside the engine. I make it 10 total in the wheels, cush, swingarm and steering head and at least 7 of those were completely shot. Oh and the nice (looking) Ohlins shocks it came with are some sort of Husqvarna motocross shocks that have had a spacer inserted to shorten the stroke, so they have to go too.
parked.JPG

I should probably switch to a "how to reassemble everything" thread - but before I do that, one last jetting question. I got my copy of the Green Book from Tim Parker (very helpful so far) - it has a short new section on Series2 Jotas like mine - just a couple of pages at the back with what changed - the very last paragraph in the entire book is pictured below. It basically says you might get a weak mixture with the S2 carbs and if you do then use a AB268 needle-jet.
Timbook.jpg

Every commenter so far has said to stick with AB265, which I have, so just wondering if anybody thinks this might be worth trying if (when the bike runs again) it's still running rough/slow return to idle. Some recent comments above about lowering needles but that weakens a rich mixture? Now that I write this down... I suppose the universe is telling me I'm going to need to know whether it's running weak or rich before I start buying new jets. Fair enough.

Oh and I did manage to TimeSert the sump plug without removing the engine - sort of leaned the whole thing over at 45degrees and sat cross-legged in front of it. Thanks for the advice above on getting that done. There were really only about 2 good threads at the top of the hole so the longer-plug method wasn't going to hold. Need to lockwire it too.
plug2.jpg

-Richard
 
Just a quick follow-up seeing as it started as a thread about jetting.

I finally got the bike back together and have put a few miles on it. I used the jetting suggested at the start of this thread:
130 main, 55 idle, AB265/K1 2nd posn.

I rode it (finally!) and it felt a bit weak at the top end, pulling up hills on the freeway etc. Then I paid attention to the link someone sent earlier [http://www.laverdamania.net/carbgb.htm] to the standard jetting tables..and saw that with 4C cams, the stock main jets were 145.

So I got a set of 142 jets (nearest size available locally right away) and - much better! Goes really well. I need to get more miles on it, check mixture properly etc, but pretty happy with how it runs now.

Shame the clutch slave bleed screw is seeping again, sigh. But that's for another day.

-Richard
 
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