It has a reley in the bucket witch is supposed to protect the switches during starting , will this work?

Higher wattage bulb for 81 R100RT?
OK, there are three determining factors in the bulb selection:
1) How much electricity (watts) will it require to operate?
1A) Will my charging system sustain the load?
1A1) How much charging output do I have?
1A2) How much of the time am I running at full charging system output?
1B) How much current is my wiring and switches capable of handling?
1B1) Do I have adequate relay protection?
1B2) Can I add relays?
1B3) Can my switches handle the added current flow?
1B4) Can I set up relays to take the current load off the switches?
2) How much heat will it generate, and is that an issue?
2A) Is the headlamp enclosed?
2B) Is there adequate cooling air to keep the headlight assembly from overheating?
3) Will it make my ride safer/brighter?

Those are the questions that you need to ask. On a 1981 R100RT, specifically, the relay does NOT protect the switches at all. It exists to shut off the headlight load during starting the bike. (that is a good thing). The handlebar switch that controls the high/low beam sees ALL of the headlight current, and even with a stock bulb, those switches can melt the plastic around the contacts. That is a known issue.

You can install the two-relay Eastern Beaver kit to protect your switches and make your lamps brighter.
http://www.easternbeaver.com/Main/Wiring_Kits/H4_Kits/h4_kits.html

THEN, you can use a higher watt bulb, as long as the bulb design puts the center if the illumination flare in exactly the same spot in your reflector/lens setup, because even small variations will cause a significant light drop-off at distance.

Higher wattage bulb for 81 R100RT?
OK, there are three determining factors in the bulb selection:
1) How much electricity (watts) will it require to operate?
1A) Will my charging system sustain the load?
1A1) How much charging output do I have?
1A2) How much of the time am I running at full charging system output?
1B) How much current is my wiring and switches capable of handling?
1B1) Do I have adequate relay protection?
1B2) Can I add relays?
1B3) Can my switches handle the added current flow?
1B4) Can I set up relays to take the current load off the switches?
2) How much heat will it generate, and is that an issue?
2A) Is the headlamp enclosed?
2B) Is there adequate cooling air to keep the headlight assembly from overheating?
3) Will it make my ride safer/brighter?

Those are the questions that you need to ask. On a 1981 R100RT, specifically, the relay does NOT protect the switches at all. It exists to shut off the headlight load during starting the bike. (that is a good thing). The handlebar switch that controls the high/low beam sees ALL of the headlight current, and even with a stock bulb, those switches can melt the plastic around the contacts. That is a known issue.

You can install the two-relay Eastern Beaver kit to protect your switches and make your lamps brighter.
http://www.easternbeaver.com/Main/Wiring_Kits/H4_Kits/h4_kits.html

THEN, you can use a higher watt bulb, as long as the bulb design puts the center if the illumination flare in exactly the same spot in your reflector/lens setup, because even small variations will cause a significant light drop-off at distance.

Supposing that you merely want more light to safely ride at night, for all the reasons listed in the prior posts, I'd suggest you focus your search on LED type lamps. In particular: 1) LED headlamp bulbs that fit the H4 socket, and/or 2) LED accessory lamps that can be mounted on your forks or "crash bars".

By using LED lamps, you'll get more candlepower output at a much lower power consumption level. This puts less stress on the switches, wiring, and alternator, and thereby makes all the very real concerns previously listed moot.

LED lighting has several distinct advantages over conventional incandescent lighting in that far less of the total energy is given off as heat, that is, a higher percentage of the power is converted into actual light. Since the bulbs run cooler, they also have much longer lives. Manufacturing advances just within the last year have made the price of vehicle LED lighting far, far more reasonable. So much so that IMHO you'd be foolish to look at traditional halogen lighting.

😉

Thank you for the info, I was about to make a mistake. Thanks for you guys it has been avoided. I will just keep the stock setup for now. I have just found out that Cree is coming out with a setup that will fit our buckets, with a fan. We will see.