Howdy gents!
Kind of a multi-question for ya today...
So recently upon instruction of you fine folks, I capped off the SRIS system on my 380J. Vacuum caps on the exhaust side and on the carb side. First attempt, all 3 of the caps on the instate side blew right off within 5 minutes of riding. The exhaust side stayed put. I replaced the intake side caps and used clips to hold them in place, and they have seemed to stay put with about 30 minutes of riding.
However, I am still noticing 2 stroke oil pooling a bit underneath the carbs atop the gearbox. Before capping everything off I removed and inspected all of the banjo fittings and check valves on the injectors and they all seem to be in order.
Any idea where this excess oil could be coming from? Considering it's found its way on to most of the surfaces in the area it's difficult to locate an origin. Could this fluid in fact be seeping from the injector fittings due to old washers? These are the plastic washers that are on each side off he banjo bolts on each injector line. Or could I possibly have a flaw somewhere in one or more of the actual injector lines themselves? Has anyone noticed this after removing the SRIS system?
Looking for any guidance I can get for troubleshooting the issue!
As always, huge thanks in advance! You guys are the best.
Cheers,
John
Injector oil seepage after capping SRIS system?
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Re: Injector oil seepage after capping SRIS system?
I'm wondering if it's excess oil that's blown out of the brass SRIS tubes on the intake side of the jugs when the caps came off, and it's pooled under the carbs.
I guess the only way to be sure of the origin of the drips is to remove the carbs, clean the top of the cases, put it all back together and see if you can spot any weeps / drips from there. It's a pain in the arse doing all that, though
A long while ago I had a slight weep from one of the banjo bolt washers on my 380M (no SRIS from the factory), but it turned out to be the bolt was a little loose. It was a smear of oil, no more than that.
I guess the only way to be sure of the origin of the drips is to remove the carbs, clean the top of the cases, put it all back together and see if you can spot any weeps / drips from there. It's a pain in the arse doing all that, though

A long while ago I had a slight weep from one of the banjo bolt washers on my 380M (no SRIS from the factory), but it turned out to be the bolt was a little loose. It was a smear of oil, no more than that.
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
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Re: Injector oil seepage after capping SRIS system?
Just a thought but is the oil you find fresh looking injector oil or oil that looks more dirty like its been through the system and then spit out by the now capped off SRIS system . Is the transmission oil a different color ?
the older i get the faster i was
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Re: Injector oil seepage after capping SRIS system?
Thanks guys!
Dave, it looks to be pretty fresh... So that would lead us to believe it is not from the SRIS system, and instead from an injector line. Great thinking! And it's blue like my stoker oil, so I'll presume it's not tranny oil. Maybe I have a loose banjo bolt down there, I will double check.
Any more ideas I'd be glad to hear them! Thanks you guys!
Dave, it looks to be pretty fresh... So that would lead us to believe it is not from the SRIS system, and instead from an injector line. Great thinking! And it's blue like my stoker oil, so I'll presume it's not tranny oil. Maybe I have a loose banjo bolt down there, I will double check.
Any more ideas I'd be glad to hear them! Thanks you guys!
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Re: Injector oil seepage after capping SRIS system?
Went through and checked that all of my banjo boots were properly tight. Had 2 semi loose ones so I tightened them up. Flew around town a bit and checked, still showing some oil atop the case
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The oil looks to be fresh as it's blue and not black like used 2 stroke oil. Could this new-ish oil be leaking from the capped recycle nipples at the carb side? I ordered some smaller caps as the ones on there aren't extremely tight (but they're staying out for now).
Alternatively is it possible that this oil is seeping from the area on the injector lines where the banjo bolts attach? I don't see any visual cracks or damage to the lines. The bikes been run regularly for about 5 years and the lines appear to be in good shape. Do the crimps at the banjo bolt ends of these lines loosen over time? Can't figure out where else it could be coming from!
Thanks guys!

The oil looks to be fresh as it's blue and not black like used 2 stroke oil. Could this new-ish oil be leaking from the capped recycle nipples at the carb side? I ordered some smaller caps as the ones on there aren't extremely tight (but they're staying out for now).
Alternatively is it possible that this oil is seeping from the area on the injector lines where the banjo bolts attach? I don't see any visual cracks or damage to the lines. The bikes been run regularly for about 5 years and the lines appear to be in good shape. Do the crimps at the banjo bolt ends of these lines loosen over time? Can't figure out where else it could be coming from!
Thanks guys!
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Re: Injector oil seepage after capping SRIS system?
Can you post up a picture ?
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Re: Injector oil seepage after capping SRIS system?
Hey Dave,
Sorry for the delayed reply. I'll try to get a photo this week if it persists after my newest scheme.
Got 0.1" vac caps, gonn run small amount of red RTV around the nipple and slide the caps on. After close examination, my only conclusion is that the oil is leaking from the vacuum caps I have on there now (no tight enough?). Hopefully this cleans it up. In lighter news, the bike IS running excellently.
Sorry for the delayed reply. I'll try to get a photo this week if it persists after my newest scheme.
Got 0.1" vac caps, gonn run small amount of red RTV around the nipple and slide the caps on. After close examination, my only conclusion is that the oil is leaking from the vacuum caps I have on there now (no tight enough?). Hopefully this cleans it up. In lighter news, the bike IS running excellently.
