Old Triumph 750 Bonneville

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Anybody know anything about these bikes or where I can go for information? My brother is about to get a nice old T140? 1976 750 Bonneville. It has disc brakes front and rear, left side shifter and under 9,000 miles. It's got good compression but has been setting for a long time and won't start.
 
A new used model is better in so many ways and will probably cost less over time.

Does he want to ride or have a excuse to whip out the 1000 piece tool kit? The old stuff was built like junk.

Dig the blue though.
 
Fun to drive and tinker with. On a unknown bike it pays off to rebuild engine and carb, pretty straight forward stuff.
Leaks oil (Some more than others) and has quirky electronics. Nice projects and weekend short trippers.

Worth keeping stock for resale value.

http://www.triumphrat.net/forum.php
 
A wonderful bike to ride. I had one and rode it to college way back, I also had a Royal Enfield 30.50(30.5 CU IN= ~ 600CC) Tomahawk. Wonderful vertical twin engine bikes.
 
Looks like a nice unmolested original that was never dropped.
The no-start problem is almost certainly caused by an ignition system fault, although the carbs could likely use a tear down.
These are said to be very nice bikes to ride although in no way fast by modern standards.
This would be a fun toy to have.
 
Back in the late 60s I rode with some riders who had them.
Beautiful bikes but needed constant tinkering.
 
I've had a '66 Bonneville for years. It used to be my daily rider, lots of fun. Definitely a hobby machine, it will take lots of TLC but worth it in my opinion. What I did was methodically go through the electrical system and get rid of everything that said Lucas on the nameplate. You could, and I think you still can, get aftermarket voltage regulators and ignition systems that are very good. If he wants to spend the money.

If it's been sitting a long time old fuel has probably gummed up the carbs. They are easy to work on.

Bottom line is that there was a reason that the original Triumph motorcycle company folded. The Japanese bikes of the era were just plain more reliable and had much better engines.

If your brother is looking for a hobby project, this might be a good one. If he just wants a neat old motorcycle to ride I'd suggest he buy one of the many newer retro bikes. In my case, the old Triumphs is just a lot of fun. Once I got it squared away I rode it across the US with the only problem being a chain replacement. But I am very close to being a professional hobbyist.
 
The only motorcycle I have ever ridden was a Bonneville TR120? from 1972? Beautiful bike. Not reliable. Last time I rode it, it almost caught on fire. the wiring harness was smoking.
 
A neat looking old bike, that required constant attention to keep running. Now that it's 40+ years old, it will be even less reliable. If he wants to tinker with it, and look at it, it's a great bike. If he wants to ride, he'd be better off getting a new replica version.
 
I would bet that once it gets started and he does a few hundred miles, it will perform like it did before it got parked. Great bike for bike nights, or just fair weather Sunday rides.,,,
 
I love that bike. Sold my right side shift Bonnie (year model before this one) to a bud that still rides it today. Yeah, he has a Goldwing for two-up with the wife to the Eastern Shore, etc. But for pure riding fun, the Triumph wins hands down
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They handle well and they'll pick the front end up any time you want if you know how to ride
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You did tickle the carbs right? If not, it won't start.

Do you know that it has spark?

You have been through all the wiring ground locations, all clean and tight, and no wires are broken?

Headlight bright?

The thing about "attention" is way overblown. You can convert to pointless ignition, but why ... Points work fine and the amount of miles you put on a year means doing one big good winter service each year and just riding.

Unlike a computer controlled motor, this can actually be fixed with hand tools. And there are "Trumpet" owners in every decent town in the USA that will give you a hand if you need it. Every Indy bike shop knows who they are and has their phone numbers.

Join the local Brit Bike Club, you'll have that thing singing in no time
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If it has compression (resistance when kicking), has spark and it's timed close, all it can be is fuel. Push the tickler buttons down until it drools just a bit from the carbs, kick it over
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If it won't light first or second kick, it's not happy. Find out why ...

It's a good investment and the value is only going up, unlike recent bikes ...
 
I don't really know anything about these bikes as I'm a Harley guy. The bike shop owner is a Harley shop, but he likes these old Triumphs too. He's selling it for the guy who owns the building and is getting old and wants to reduce his collection. I'm meeting with him Monday. My bro lives in WV so I'm handling the transaction.
 
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It has oil in-frame. Open the seat and take off the oil cap. Stick finger in big hole. Come out with oil. If it looks good, it prolly is.

There are buttons on top of the float bowls. The gas may be bad ... Drain tank and put in fresh. Turn on gas. Push buttons down on carb until it drools a little (don't need much). With battery full and tranny in neutral, crack throttle 1/4. Pull out kick starter, swing through until you feel compression. Let starter lever go back to top. Left foot on peg, right foot on kick starter. Give it a he-man push like about a half jump down. Motor will spin and prolly cough. Do it again and it'll be running
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If not, find out why ...
 
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