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Yes my 2017 Harley Davidson RG with the M8 107 (with an aftermarket 117" stage 4 upgrade installed)
Engine overheated while riding on the highway for over an hour, lost power & engine sumped.
Pulled over & checked oil & it was down 1 quart !
The engine never recovered from this & is now back at the shop.
Called the dealer & they said it must be a bad tune ? Which is BS !
Now after researching, I guess most of the M8 107's with any 3 & 4 stage upgrades are reporting engine oil sumping !
Is Harley Davidson MoCo going too issue a recall on all M8 107's engine's ?
Or at least ----- are they going too stop selling their stage 3 & 4 upgrade kits ?
let me know if your having the same problem & what you think ?
As long as you used the screaming eagle tuner and have not changed to aftermarket headers or a cam the moco should make it right. The stage 4 seems to be the most common sumper
Called the dealer & they said it must be a bad tune ? Which is BS !
You're probably right. But since you installed an aftermarket 117" kit, your warranty's void and your dealer and Harley are off the hook. If you had used a Harley Stage IV kit, installed by a Harley dealer, then they would have replaced the engine for free, under warranty. Without that warranty, I can certainly see that the dealer is likely to blame the aftermarket parts for causing the problem. It seems unlikely that they did, but -- who can say?
Now after researching, I guess most of the M8 107's with any 3 & 4 stage upgrades are reporting engine oil sumping !
I don't think that's an accurate representation at all. It's more accurate to say that very few engines are sumping at all, and of those that do, a disproportionately high percentage of them seem to be CVOs or those with Stage III or Stage IV kits.
There's no way for us to know what percentage of M8 107's with Stage 3 or 4 are sumping, versus the percentage of stock M8 107s that are sumping. We do know it happens to both. It seems to be more commonly reported on the CVO (especially the CVO Stage IV), and also on others with Stage III and Stage IV, than it does to stock bikes. But even so, the total percentage of bikes that have sumped, versus those that haven't, still seems to be quite tiny.
Is Harley Davidson MoCo going too issue a recall on all M8 107's engine's ?
Almost certainly not, although I do think if someone were to be seriously injured (or worse) due to sumping kicking in when they were, for example, trying to pass some cars on the freeway... then the NHTSA might force them to address the issue. Otherwise, probably not.
Or at least ----- are they going too stop selling their stage 3 & 4 upgrade kits ?
That remains to be seen. I will say that if they do stop selling them, then that would be an indication that the repair issues were costing them more than it's worth. But if they keep selling them, then that's probably an indication that there aren't that many Stage 3/4 kits causing sumping that they then have to deal with.
I bought 2017 RGS had them install Stage 3 as the Stage 4 and not been made available in late 2016.
107 to 114 Stage 3 SUMPED
The bike sumped a few times and MOCO offered to pay to upgrade to Stage 4 if I paid for kit.
Being a power junkie I paid for Stage 4 kit and they installed.
This build SUMPED
Sumped 3 times and MOCO took it apart had lead tech from MOCO (Warren) come and mess with it.
They ended up installing new motor and new Stage 4 kit, guess what,
it SUMPED too.
I learned to keep a quart of oil with me and when it sumped just remove crank sensor, let oil out and top off.
2 years goes bye and the CVO was looking attractive.
So I asked dealer, did they fix sumping issue, of course they said oh yeah. New 5th Generation oil pump and Cam Plate with seal. Its definitely fixed. So I traded the 2017 for the 2019 RG with 117.
Im thinking thank god im out from underneath that other POS.
Well 160 miles into break in.
117 SUMPED, (dealer said a ring broke and a piece got stuck in o pump) it damaged the cylinder so the MOCO was going to replace topend under warranty.
since I was told it sumped due to broken parts I was still under assumption that M8 sumping was a thing of the past.
I bought Stage 4 kit and got it installed for free (because warranty was rebuilding topend anyway)
It has SUMPED 4 times and the compensator failed too but we are talking about sumping.
Dealer put me on demo bike, a stock 114 and it was doing great for 2 weeks, but hey its an M8 and you know
It SUMPED.
The moral of this post.
SUMPING IS NOT AND ISOLATED ISSUE.
ITS AN M8 ISSUE
DO NOT BUY.
unless of course only your speed limit obeying grandmother plans on riding the bike.
PS the bike is still in shop getting new motor and Stage 4 kit over 3 weeks now 50 Thousand Dollars The M8 Sump hole
Originally Posted by FatBob2018
You're probably right. But since you installed an aftermarket 117" kit, your warranty's void and your dealer and Harley are off the hook. If you had used a Harley Stage IV kit, installed by a Harley dealer, then they would have replaced the engine for free, under warranty. Without that warranty, I can certainly see that the dealer is likely to blame the aftermarket parts for causing the problem. It seems unlikely that they did, but -- who can say?
I don't think that's an accurate representation at all. It's more accurate to say that very few engines are sumping at all, and of those that do, a disproportionately high percentage of them seem to be CVOs or those with Stage III or Stage IV kits.
There's no way for us to know what percentage of M8 107's with Stage 3 or 4 are sumping, versus the percentage of stock M8 107s that are sumping. We do know it happens to both. It seems to be more commonly reported on the CVO (especially the CVO Stage IV), and also on others with Stage III and Stage IV, than it does to stock bikes. But even so, the total percentage of bikes that have sumped, versus those that haven't, still seems to be quite tiny.
Almost certainly not, although I do think if someone were to be seriously injured (or worse) due to sumping kicking in when they were, for example, trying to pass some cars on the freeway... then the NHTSA might force them to address the issue. Otherwise, probably not.
That remains to be seen. I will say that if they do stop selling them, then that would be an indication that the repair issues were costing them more than it's worth. But if they keep selling them, then that's probably an indication that there aren't that many Stage 3/4 kits causing sumping that they then have to deal with.
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M8 Sumping
