7750 Power Reserve Problem

[Keniath]

Hello.
So i recently bought a Hublot Big Bang V6 6.5 with a A7750 movement. Power reserve was good the first few days but now its starting to be terrible. Im really disappointed.
Even when i go out and wear it all night moving around it doesnt even last 8 hours and i find it stopped when i wake up.
What would you advise me to do? Is it possible to service and is it worth it? Or should i try to get a new movement?
What would a gen 7750 cost? If i get a new movement rep or gen does the decoration plate and rep hublot rotor fit back in?
Many questions...

 

[mauricio612]

You can wind your watch before wearing it or before going to sleep until you get this issue sorted.

You probably need to have that watch serviced. I have had 1 7750 watch serviced before and it was worth it. Usually the price is between 180 and 220€.

Getting another ''unserviced 7750'' might lead to the same problem so I would not opt for that option.

Getting a gen movement will be more expensive than servicing it and you need to source a gen chrono second hand. Gen Valjoux 7750 is quite expensive - I have seen some used ones sell for about 450-500€. Then you need to pay for a watchmaker to install it.

As for the rotor, I am not sure so I'll let the watch experts talk but I have always seen the Franken watches owners with gen Valjoux Chrono keep the gen rotor which sometimes leads to a ''Longines'' decoration in a Breitling watch

I am sure they have a good reason for that, probably the swiss rotor is better than the asian one...

 

[GreenTooth]

A gen 7750 should hold power for more than 40 hours, I guess the rep should be more or less similar. Try and wind the watch by hand fully one night, and see how it holds up, the rotor doesn't really wind the watch all that much, it takes a lot of time to fully wind it, especially if you are not moving a lot. If it still doesn't hold a charge the first thing you should look at is the mainspring, might need a clean, might need a new mainspring if it's broken or kinked. It's alway better in my mind to try and fix the movement. A gen 7750, as far as I've seen is around 300$ on ebay on a good day, they are usually more expencive, but you might get lucky. Chinese reps go for around 120$. For the rotor and the decoration plate I can't comment, my guess is that it should, but there are quite a few variations of the 7750.

 

[Rx4Time]

My gen 7750 cost $450 from Otto Frei. It's got roughly 48 hours power reserve. I've done one Asian to ETA swap in my Skyland Avenger. I had to source a gen handset so all in it cost me close to$700 installed. Some watchsmiths will swap the Cannon pinon so you can use the rep hands or crimp the second hand post. I was advised against this as the metal is fragile. In yours I'm not sure that a gen seconds hand would work as the big bang uses an in house movement. Best option is service it and enjoy. I've had two Asian 7750 serviced and the difference is night and day. More economical and you will have a reliable watch for years to come.

 

[Keniath]

Thanks everybody for the quick and detailed answers. You guys are awesome!
Looks like i will send the watch for service. Any suggestions for somebody reliable to do that in Europe?
If you are not allowed to write names please let me know though pm. Thanks

 

[UDTMIKE]

I just received a Skyland Chrono last week. It ran for 20 minutes then stopped. I sent it off the be checked and serviced etc. He found a piece of styrofoam in it. It had jammed the gears. Was not the TD's fault, he ran QC on it before he shipped it out. But now it's running strong and is fantastic. But it is a 7750, time bomb

 

[Keniath]

A gen 7750 should hold power for more than 40 hours, I guess the rep should be more or less similar. Try and wind the watch by hand fully one night, and see how it holds up, the rotor doesn't really wind the watch all that much, it takes a lot of time to fully wind it, especially if you are not moving a lot

How many turns should I count roughly to fully wind it ? Is it possible to over wind a 7750?


Sent from the RWI mobile app

 

[GreenTooth]

How many turns should I count roughly to fully wind it ? Is it possible to over wind a 7750?


Sent from the RWI mobile app

It is impossible to overwind any automatic movement, these movements are constructed in such a manner to prevent it. I think good 30 - 40 turns should definitely wind it up. But like I said there is no limit to winding it, although by sitting and twiddling the crown all day you could theoretically cause exes wear... but you would really have to be determined to break the watch in that manner.

 

[Rx4Time]

dmuit is in Germany. ado213 in UK. The 7750 is a reliable movement when in it's native configuration. Issues usually arise when the running seconds hand is moved from the 9 o'clock placement. The problem is the transfer module and geartrain to move the subdial position.

 

[Keniath]

The Hublot Big Bang has a seconds @9 configuration.
I'll try winding it manually to see how long it lasts. But I'll definately send it for servicing. Probubly to Domi as iv heard only good words from everyone [emoji4]


Sent from my iPhone using RWI

 

[simbarn]

Yes wind it as everyone has said to see if the mainspring actually can support 40 plus hours of running. Check the rotor; does it spin with little effort, can you hear it spinning over and over with a little spin?
I have pulled a few of my A7750'S down and they have NO oil in them plus crap. They all need a good clean and the correct oiling, plus the mainsprings are not oiled either, so no wonder issues pop up frequently with these.
When you buy a replica watch you are literally buying an unfinished timepiece, missing the time someone has spent disassembling, cleaning, reassembling, adjusting a watch to positions and finally setting its rate. This all takes time and experience!

 

[Keniath]

I stopped having this problem because I upgraded my rotor to an engraved one I bought here on the forum. So now my watch winds very good with normal wear

Sent from the RWI mobile app