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Shiftcam Sketchy Starting?

wbrownell9

New member
Anyone besides me have troubles with their Shiftcam not starting? 2020 GSA with 16,000 miles. The symptom is that it spins about a half turn then stops. Battery has been replaced under warranty. Generally it gives me no trouble but two situations are problematic. One is, oddly enough, if it's spent time on a charger (CTEK MXS 5.0), the other is if it's warmed up then shut down and set for a few minutes. As long as it takes to get gas - no problem. As long as it takes to get something to eat - no problem. Somewhere in between - problem. If it's cold (just off the charger), it helps to turn it off and turn it on again. If it's hot the only solution is to wait for it to cool down although one time I had some folks push me so I could bump start it.


I had a 2015 RT that developed issues for a while, it would spin but not catch. Try a second time and it would catch immediately. That issue went away after a month or so and never returned. I expected the same from my 2016 GSA but it never happened - it never ever failed to start immediately on the first push. I replaced the OEM battery after 135,000 miles but when turning it off waiting in line for roadwork I never worried about it not starting. But the 2020 GSA just won't spin. I'm reluctant to take it on trips for fear I'll have the choice of idling for 20 minutes or holding up traffic trying unsuccessfully to start it. Or some morning I'll come out and it'll act up for no apparent reason. It's fine 99% of the time but that 1% failure rate does nothing for my trust in the machine.


I'm no gearhead but the only thing I can think of is that the compression release isn't releasing. That would explain the warm engine issue but not the cold one. The other possibility is it doesn't like something about the Neutrino power module.
 
No spin on a hot engine would point to something in the battery to starter circuit and it would be something impeding current flow. A good dealer should be able to solve this. I do not have a wiring diagram for a 1250 so I am not sure of all of the components involved in that starting circuit, but again, a good dealer should.
 
You said, "it spins". What spins, the engine, just the starter? Your description is a bit vague.

If the engine spins 1/2 a turn then stalls but the starter is still trying, then the starter or battery is weak, or perhaps some bad connection in the starter/battery circuit. A new battery is no guaranty of a good battery.

Is there compression releases on the Shift cam?
 
You said, "it spins". What spins, the engine, just the starter? Your description is a bit vague.

If the engine spins 1/2 a turn then stalls but the starter is still trying, then the starter or battery is weak, or perhaps some bad connection in the starter/battery circuit. A new battery is no guaranty of a good battery.

Is there compression releases on the Shift cam?
R1200 starter made the engine go around and around and around and around, but it wouldn't catch.
R1250 just goes "Gr". As if it's running up against something that keeps it from completing even part of one revolution.

You raise an interesting point, I can't tell if the starter is fine and engaging properly but something about the engine is preventing it from turning, or if the starter motor itself is getting hung up somehow.

Yes, wetheads and shiftcam (and possibly earlier oilhead engines, too, IDK) have automatic compression release.
 
Anyone besides me have troubles with their Shiftcam not starting? 2020 GSA with 16,000 miles. The symptom is that it spins about a half turn then stops. Battery has been replaced under warranty. Generally it gives me no trouble but two situations are problematic. One is, oddly enough, if it's spent time on a charger (CTEK MXS 5.0), the other is if it's warmed up then shut down and set for a few minutes. As long as it takes to get gas - no problem. As long as it takes to get something to eat - no problem. Somewhere in between - problem. If it's cold (just off the charger), it helps to turn it off and turn it on again. If it's hot the only solution is to wait for it to cool down although one time I had some folks push me so I could bump start it.


I had a 2015 RT that developed issues for a while, it would spin but not catch. Try a second time and it would catch immediately. That issue went away after a month or so and never returned. I expected the same from my 2016 GSA but it never happened - it never ever failed to start immediately on the first push. I replaced the OEM battery after 135,000 miles but when turning it off waiting in line for roadwork I never worried about it not starting. But the 2020 GSA just won't spin. I'm reluctant to take it on trips for fear I'll have the choice of idling for 20 minutes or holding up traffic trying unsuccessfully to start it. Or some morning I'll come out and it'll act up for no apparent reason. It's fine 99% of the time but that 1% failure rate does nothing for my trust in the machine.


I'm no gearhead but the only thing I can think of is that the compression release isn't releasing. That would explain the warm engine issue but not the cold one. The other possibility is it doesn't like something about the Neutrino power module.

I have noticed that same thing.
I have 8K miles on my 2020 RT and once in a while (maybe three times in its life) it has done that. IMO its a compression issue or a piston position issue after turn off. Just letting go of the starter and trying again it started right away. This is a high volume cylinder with big pistons that need to be moved up to and past TDC to get started. At app. 625 cc per cylinder this is almost two and a half times the fill amount of the 1600 six cylinder. (Without getting into any discussions about short and long stroke engines or piston sizes vs travel distance, etc.)

A query to my Dealer Of Choice (DOC) revealed no additional info. The thought was tabled that possibly the OEM (cheap, but not the price, of course) battery does not furnish enough CCAs (Cold Cranking Amps) or CAs to reliably move all that compression, even with supposedly installed auto compression release. By the time it auto-releases the compression the piston has already reached the compression block resulting in the momentary engine freeze.

I am currently exploring replacing the battery with one with more oomph. My DOC could not help. If anybody here knows the CCAs of the OEM battery, that would be helpful. The dealer does not know, and the aftermarket will only sell you their "far superior product" without telling you how much superior compared to the OEM. I want to stay with the glass mat construction so as to avoid all the issues with the Lithium Ion stuff.

Like I said, just MHO.
 
I am currently exploring replacing the battery with one with more oomph. My DOC could not help. If anybody here knows the CCAs of the OEM battery, that would be helpful. The dealer does not know, and the aftermarket will only sell you their "far superior product" without telling you how much superior compared to the OEM. I want to stay with the glass mat construction so as to avoid all the issues with the Lithium Ion stuff.

Like I said, just MHO.

I have a Yuasa YTX20CH-BS it's 270 CCA in my 14R1200RT, I believe it's the same size as the 2020. Fits perfect same as OEM
 
I am currently exploring replacing the battery with one with more oomph. My DOC could not help. If anybody here knows the CCAs of the OEM battery, that would be helpful. The dealer does not know, and the aftermarket will only sell you their "far superior product" without telling you how much superior compared to the OEM. I want to stay with the glass mat construction so as to avoid all the issues with the Lithium Ion stuff.
This battery fits and functions perfectly.

I replaced my OEM battery on my '16RTW in 2019 with this one and it's a good price $52.50.

https://tinyurl.com/y7el3rjl
Battery%20Size-M.jpg

E6343165-F700-452E-BDD4-5F3793479902-M.jpg
 
I had the same (occasional) issue with my 2019 RT. Did with my 2009 GSA as well. On my RT, I swapped out the POS Exide (on my dime and well worth it) for one of these https://www.batteriesplus.com/produ...-88F6L0enx.hcyUIfmRBwpg&affiliate=TnL5HPStwNw

Never had an issue again. BIG difference in how it cranks over. Also cleaned all the connections and cleaned/tightened the ground while installing new battery. Hope it helps!

Are the dims the same as OEM? Looks like a great solution..
 
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