What are some good ways to pace yourself for a 150 mile bike tour you have not trained for?

It will be 80 miles over two days. Haven't trained or practiced! I'm not completely out of shape. It's not a race but I want to complete both days. Any tips?

Add this to what bikernoj stated:

Your going to have problems. There are two issues you may not over come:
1. Being conditioned enough to make 80 miles.
2. Being accustom to your bike so your back, neck, butt, arms, hands, feet don't get so sore, tired and numb you can't continue.

Couple this with back to back rides and you are doomed, bud. If you somehow make it through day 1 you won't be able to even get on your bike on day 2. If you don't have at least a couple weeks to get in minimal cycling shape you should pass on this.

These things take training, so perhaps you should have thought of that BEFORE the ride. If it's in someplace like California, it will be easier than if it's in Colorado.

Despite your obvious lack of commitment, I'll give you what I can. Give it your best shot, and see how well you do anyway.

Remember- it is NOT the time to work on your tan OR your diet! Wear SPF 200+ on every inch of your body, drink enough that you pee at EVERY stop, and eat constantly. Stretch often, make sure your bike fits properly and is well-tuned, and wear good bike shorts. If you can afford it, get a massage the first night! Drink more than you think is reasonable after each day, and be prepared for the "flushing" that will follow.

Other than that, you're on your own. But don't be surprised if you bonk, puke, cramp, or simply give up. Willpower will only go so far if you haven't trained for such a ride.

OMG. You're dead meat.

40-50 miles you could get away with. But unless you're in great shape you'll be in real pain if you make the first 80. And 80 the next day I wouldn't wish on my worst enemy. Three weeks of 1 to 2 hour rides 3-5 times a week would be the minimum training anyone in OK shape would need.

If you have to do it (why?), pace yourself as slow as possible. 8 hours each day minimum and slower if you can get away with it.

Cadence is everything. Get into a comfortable, sustainable rhythm and ignore your speed. Keep it high: spin, don't mash.

Rest very, very often...at least every ten miles and hydrate every time.

Get off the bike and walk around each time you stop!

Get bike shorts with a thick gel insert in the crotch.

If you don't have cleats wear the stiffest soled shoes you have.

Eat every chance you get even while you ride.

Bring a few gel packs for a super quick energy boost when you start to bonk (and you will).

Load up with carbs before you start.

Make sure you eat as much as you can at the end of the first day: protein not fat.

Learn how to ride a paceline or at least how to suck somebody else's wheel.

Take every spare ounce off your bike and use the sag wagon to carry your gear if the tour has one.

Put another water bottle on the bike and drink, drink, drink.

Good luck!

Ride at a pace that's comfortable for a 90 minute ride. That will probably be close to the time between rest stops on the ride. Get off the bike at each rest stop for about 10 minutes. Eat and drink something at each stop. Make sure to drink while riding.

Good luck. You'll need it.

HTH

Stay home, you will wish you had if you try it. Otherwise, just take a nice easy pace that does not tire you too much.