Possible kickback solution?

[Janne339]

If the fuel injection system shuts off when voltage drops below 10 volts, then a new ecu flash not goona make my sled any easier to fire up.

I gonna log some more files when I fire up the engine, when cold and warm.

 

[mtotguy]

My sled ('14) had the kick back problem bad. I went thru 3 starters. It didn't matter how long I held the key. It didn't matter if it was very cold out or warmer. It didn't matter if I skipped the prime cycle. It still did it. I suspected voltage drop and changed to heavier battery cables. I also went to the EVO re-flash. I rode it all year last year without a kickback. I don't know which fix was actually the fix. Maybe both. Now that being said the engine will occasionally stall the starter. But it isn't the horrible sounding kickback as before and it doesn't seem to hurt anything. It only took 2 or 3 kickbacks to ruin a starter.

 

[Janne339]

Is it possible to temporary try with a powerful battery and shorter cables. So the voltage to ECU and ignition system not drop? Only for comparison?

 

[NOS-PRO]

My sled ('14) had the kick back problem bad. I went thru 3 starters. It didn't matter how long I held the key. It didn't matter if it was very cold out or warmer. It didn't matter if I skipped the prime cycle. It still did it. I suspected voltage drop and changed to heavier battery cables. I also went to the EVO re-flash. I rode it all year last year without a kickback. I don't know which fix was actually the fix. Maybe both. Now that being said the engine will occasionally stall the starter. But it isn't the horrible sounding kickback as before and it doesn't seem to hurt anything. It only took 2 or 3 kickbacks to ruin a starter.

I'm with mtotguy - Ever since my EVO flash....no worries, fire up less than 1 crank and always idled perfect. I just did this test under the latest 2016 flash from Yamaha. Just for the record...I have 2 ECU's. The EVO stage 4, then I had the 2015 which kicked back and now the 2016 was flashed to eliminate the 2015....no kick-back, but takes 2 times to start usually.

 

[titanrcr]

My sled ('14) had the kick back problem bad. I went thru 3 starters. It didn't matter how long I held the key. It didn't matter if it was very cold out or warmer. It didn't matter if I skipped the prime cycle. It still did it. I suspected voltage drop and changed to heavier battery cables. I also went to the EVO re-flash. I rode it all year last year without a kickback. I don't know which fix was actually the fix. Maybe both. Now that being said the engine will occasionally stall the starter. But it isn't the horrible sounding kickback as before and it doesn't seem to hurt anything. It only took 2 or 3 kickbacks to ruin a starter.

Do you know for sure that your 14 didn't have the updated flash? If you had purchased it as a leftover the dealer may have done the flash already. I didn't think the 14's had the kickback issue unless they got the updated flash to cure the "hot start" issue. As for the EVO flash curing the kickback, The EVO flash uses the stock 14' start-up mapping.

 

[titanrcr]

Can you please tell us the conditions that were present when your Kickbacks occurred? Was the sled cold? What was the temperature outside? Did the sled seem slow to turn over verses when the sled was warm?

Ambient temp doesn't matter, has occurred with both a hot and cold engine. Engine has never turned over fast enough for my liking.

 

[Janne339]

My sled ('14) had the kick back problem bad. I went thru 3 starters. It didn't matter how long I held the key. It didn't matter if it was very cold out or warmer. It didn't matter if I skipped the prime cycle. It still did it. I suspected voltage drop and changed to heavier battery cables. I also went to the EVO re-flash. I rode it all year last year without a kickback. I don't know which fix was actually the fix. Maybe both. Now that being said the engine will occasionally stall the starter. But it isn't the horrible sounding kickback as before and it doesn't seem to hurt anything. It only took 2 or 3 kickbacks to ruin a starter.

Mtotguy,
What cables do you changed?

 

[Mike P]

I don't believe it's a voltage drop issue that's related to the battery being located in the rear. I installed an engine, wire harness and ECU from a Nytro in the viper chassis with the battery still located in the rear and it fires up flawlessly like the Nytro's always have. My belief is that the Arctic Cat ECU is flawed and it may be beyond a simple flash to correct it. I recently replaced my ECU on a 2014 Harley Street Glide with an aftermarket ECU. The Harley ECU is not flawed but there is only so much you can do with flashing it. We know what works but I'd be surprised if Yamaha ever goes back and properly corrects the sleds already out there.

If the ECU in your video is happy with the voltage supplied to it then it will perform as it was designed. If the ECU in the SR Vipers is not happy with the voltage supplied to it then it will not perform as designed. All electronic equipment is designed differently. Some are designed to tolerate situations that others fail in. Did you happen to test the voltage at the feed to the ECU while starting your sled. Was the motor warmed up? Was that you first time cranking it over?

 

[cannondale27]

Do you know for sure that your 14 didn't have the updated flash? If you had purchased it as a leftover the dealer may have done the flash already. I didn't think the 14's had the kickback issue unless they got the updated flash to cure the "hot start" issue. As for the EVO flash curing the kickback, The EVO flash uses the stock 14' start-up mapping.

There has been many 14's that had starter failures. Once enough EVO flashes get out there then I will be a believer. Not till then. Also if the EVO flash does prove to be successful in stopping kickbacks is it the tune or is it the process of installing the tune which is better? If it's just the tune a PCV can also do that. I believe EVO uses the 14 program but changes entire fuel and ignition map. Maybe they are just to lean at start stock. The thing that makes me doubt Yamahas process of flashing is that 14's had lots of code errors like the crank spike code and the random nonexistent idle. I have not heard any reports of those happening with EVO flash either. EVO doesn't touch any of the base map/code which would effect that yet it seems to be gone with thier flash. 15 flash did take care of that and hot start issues.

 

[grizztracks]

If the battery voltage drops below 10 volts on this Yamacat system it shuts off the fuel injection & does some goofy thing to the ignition timing. Not saying it's the kick back issue, but it surely doesn't help it.

This makes me wonder if the Cat ECU tolerances are not that stringent and some units are extremely sensitive to the voltage drop caused by starter draw. It may explain why there are inconsistencies from sled to sled. It would be interesting to know if a Viper that has had multiple failures could be corrected with an ECU swap from a Viper that hasn't had starting issues.

 

[titanrcr]

There has been many 14's that had starter failures. Once enough EVO flashes get out there then I will be a believer. Not till then. Also if the EVO flash does prove to be successful in stopping kickbacks is it the tune or is it the process of installing the tune which is better? If it's just the tune a PCV can also do that. I believe EVO uses the 14 program but changes entire fuel and ignition map. Maybe they are just to lean at start stock. The thing that makes me doubt Yamahas process of flashing is that 14's had lots of code errors like the crank spike code and the random nonexistent idle. I have not heard any reports of those happening with EVO flash either. EVO doesn't touch any of the base map/code which would effect that yet it seems to be gone with thier flash. 15 flash did take care of that and hot start issues.

I didn't realize the 14s were having trouble with failing starters, I just wish Yamaha would come through with the fix for us before another season passes. It's really starting to get old.....

 

[cannondale27]

I didn't realize the 14s were having trouble with failing starters, I just wish Yamaha would come through with the fix for us before another season passes. It's really starting to get old.....

They did. The 17 flash is thier solution. Sounds like it helped those with kickbacks but made the starting situation worse.

 

[skidooslayer687]

Just going threw the process of having mine reflashed now...

A little history on my sled, its a 14, full hurricane/hindle kit on it with the PC5. The first year I got it (13) It always started perfect, no kickback issue, no hot start issue, no codes. I always turn my key on and let it prime then start it. Going into the 2nd year of riding the original reflash was done by the dealer, right away I noticed a different idle (almost like it had a cam in it lol) and that famous "blurp" just above idle that sounded like a stutter box almost. However, the sled never failed to start hot or cold, always started strong and almost no hesistation. About mid winter last year is the first time I've ever had any starting issues at all, cold starts the motor wanted to roll longer, kick, kickback and then sometimes would fire up and sometimes would need to cycle the key again. Hot starts also presented a problem and this came before the cold starts became an issue, on hot starts it would roll and roll, would not kick at all, sometimes would backfire, it would need a key cycle off and then retry to get it to start and it would always start. Last spring I took it to the dealer and complained of these issues as they'd never happened before to me, they were great about it, replaced the starter and drive no questions asked and I was told at that time about this update coming.

So I dropped the sled off at the dealer, they did the update on it... And now its having the common problem of having to roll it, in which it fires but doesn't stay running and then the key cycle off and then retry it which it fires up. I will say it does sound better, it doesn't have the kickback sound to it. I went to have a look at it as the dealer said it was ready and this is when I found out how it started. Basically told them that it never has acted like this, and it always started very strong without hesistation... There still looking into the problem, tests have been done on it, now what has been done Im unclear... Tried different things I know for sure such as unhooking PC5 from system and it did not make a difference at all.

Its interesting reading all the info with these problems with starting, I don't understand why Yamaha cannot figure it out, and there doesn't seem to be an exact cause, some sleds do it, some don't.... Mine never had a single issue at all till last winter, what happened I have no idea but definitely know it never did it before with the original flash it came with or the 2nd one they came out with

 

[Mike P]

8

Valve clearance / decomp clearance and throttlebody sync are the variables I believe are the clincher. Only because very few check either.

The engine is rated very high in the industry. The fact is if there was only one minor issue then most likely this thread would not exist. It seems that with all of the input over the last few years we need to be looking at fine details.
If it were only the battery location then the trouble would be the same from sled to sled however if you add TB-Sync then it presents in a different way. Both issues would seem minor on there own. I'm sure most people will look at a problem with there sled and run thru a simple cause and affect, end up with the conclusion:
"that can't be it because mine doesn't do that"
If there are multiple minor issues and some of us have more of them than others that seems to fit the type of results we are having. I have read a lot of threads on TY related to this subject and I'm sure there are some guys that could put together a list of minor issues that on there own would not create a problem in which the sled would be disabled and some times could go unnoticed, but when two or more exist together they would become serious enough to disable the sled. This requires a fare amount of knowledge, patience and a firm understanding of the engine and ignition system. A check list of sorts, DIY with the right tools.
Unfortunately I'm sure some components like the ECU will be more of a challenge.

 

[Mike P]

My sled ('14) had the kick back problem bad. I went thru 3 starters. It didn't matter how long I held the key. It didn't matter if it was very cold out or warmer. It didn't matter if I skipped the prime cycle. It still did it. I suspected voltage drop and changed to heavier battery cables. I also went to the EVO re-flash. I rode it all year last year without a kickback. I don't know which fix was actually the fix. Maybe both. Now that being said the engine will occasionally stall the starter. But it isn't the horrible sounding kickback as before and it doesn't seem to hurt anything. It only took 2 or 3 kickbacks to ruin a starter.[/QUOTE

This makes me wonder if the Cat ECU tolerances are not that stringent and some units are extremely sensitive to the voltage drop caused by starter draw. It may explain why there are inconsistencies from sled to sled. It would be interesting to know if a Viper that has had multiple failures could be corrected with an ECU swap from a Viper that hasn't had starting issues.

Good idea.