[justanothernoob]

need some sage advice please ...

Rectifier on my Ducati Monster S4R blew. A common upgrade is to go with a Shindengen MOSFET regulator - usually the FH012AA or FH022AA. There's a new rectifier out - the SH847AA which is a series style MOSFET so it places less stress on the stator and opinions seem to be that it's an even better choice. The price difference is negligible so I went with the FH847AA. Unfortunately though it's slightly larger so doesn't fit into the usual location (under the seat) so I'm considering alternative mounting points and need some help.

Option 1: place it on the left of the front cylinder, behind the fan (pics 1 & 2).
Pro's are it'll get plenty of cooling; because it's down by the engine it doesn't look out of place.
Con's are I'll need to make up a bracket but that shouldn't be too big an issue; not sure how hot the regulator will get and whether that will be an issue for the cable that will sit behind it(see pic #2)?


Option 2: place it under the rear subframe. This seems to be a common alternative (pics 3 & 4).
Pro's are it'll get plenty of air cooling; I can mount it with bolts and large washers so won't need to make a bracket; I'm planning to chop the rear tail anyway so another option would be to mount it to the back of the number plate?


Option 3: mount it under the lower tree on the forks (pics 5 & 6).
Pro's are it'll get plenty of cooling; there are already two bolts there (see pic #6) that just happen to be perfectly spaced so no need to make a bracket - just need slightly longer bolts.
Con's are it's noticeable and doesn't quite look right but maybe only to my pernickerty eye?


Option 4: mount in the tool-holder compartment on the underside of the seat (pic 7).
Pro's are it won't require any brackets.
Con's are it'll be pretty much jammed in there and I'm not sure how hot the regulator will get and if it'll melt the plastic or needs air flow to keep it cool?


Every option will need me to extend the loom - I'm happy soldering etc., … but I'm no auto-electrician so not sure what gauge / spec cable I'll need or if there are any limits on length etc., …?

Appreciate all advice

 

[virgilante]

I took option 2, didn't blew yet, just for fun!

 

[Mojo66]

Hi there,

I had the same issue as you on my 08 Monster S4RS, it also fried the stator

I went with the under seat option but chose to use the CORSE DYNAMICS Voltage Regulator Relocation kit for Monster 00-08 (Bellissimoto $24,95) it requires deleting the crankcase breather box. And you also will need to add filter to your crankcase breather. Completely plug and play no cutting or soldering required. They even include the zip ties

https://www.bellissimoto.com/parts/...voltage-regulator-relocator-for-monster-00-08

L8tr
Pete

 

[orionengnr]

I went with under-seat on my S4RS. The MOSFET type doesn't seem to generate the heat the original did, so airflow is not as critical. I honestly don't know how the eat base doesn't melt on the stocker.

Do a search; there is a tread on a Triumph wiring harness that is a plug and play. Costs about $11. If I can find the part number or the thread I will post it later.

 

[GoHamInHogHeaven]

I bought a mosfer rectifier and mounted it in the original location. Barely even gets warm. Definitely either relocate or replace it though, mine caught fire about a month ago.... Bike was fine, scary nonetheless and could have been much worse.

 

[duc96cr]

The PO of my S4RS mounted 2 units, one under the seat, the other under the rear , sort of back to back, so you can unplug one and plug in the other. Both are stock units. Ive never had to switch them.

 

[etienne_]

I also just fried my stock voltage rectifier, in the f*ckin middle of nowhere, Saturday night, and after 21 hours of traversing the whole mediterranean sea in a ferry. Fun times.

I temporarily replaced it with an OEM part but, for peace of mind, I will change that with a MOSFET unit from a SuperSport 939 (Part no. 54040301B, it's a Shindengen FH020AA) I just found on Ebay.

As far as my local Ducati specialist told me, it makes little to no sense to move the stock unit, because it will fail at some point anyway, and it is also pointless to mount MOSFET units anywhere else than the original placement because they don't overheat.