Triumph Rat Motorcycle Forums banner

1 - 20 of 43 Posts

·
Registered
Joined
·
7,994 Posts
Discussion Starter #1
Just picked up MCN on my way home. There is a section in the "mole" new bike news claiming test riders have been spotted out and about on a big bore replacement for the Thruxton. says it looks the same with minor detail and mechanical changes. pics coming soon they say.
 

·
Registered
Joined
·
616 Posts
Just picked up MCN on my way home. There is a section in the "mole" new bike news claiming test riders have been spotted out and about on a big bore replacement for the Thruxton. says it looks the same with minor detail and mechanical changes. pics coming soon they say.
And what they SHOULD (but won't likely) do is offer those cylinders as an upgrade kit to those of us 865ers who would like a little more punch than a stock Bonnie.

I'm not holding my breath.

I suppose there's still always Wiseco.
 

·
Registered
Joined
·
594 Posts
Just picked up MCN on my way home. There is a section in the "mole" new bike news claiming test riders have been spotted out and about on a big bore replacement for the Thruxton. says it looks the same with minor detail and mechanical changes. pics coming soon they say.
These guys must have really good eyesight or maybe they're spies from the factory, but I think I'd have a hard time spotting bigger cylinders on a moving Thruxton. Wouldn't they look pretty similar on the outside?

I do hope this is true though, because the Thruxton really should have had more of a hot rodded engine from the start (higher compression, hotter cams, etc).
 

·
Registered
Joined
·
693 Posts
I do hope this is true though, because the Thruxton really should have had more of a hot rodded engine from the start (higher compression, hotter cams, etc).
+1, and it should be put on a diet. Loosing weight can make a big difference in performance, I'd like to see it in the weight range of the 675.
 

·
Registered
Joined
·
594 Posts
The radiator will give it away.
Are you thinking the engine from the new Thunderbird has been stuffed into a Thruxton? I hope that's not the case, a water cooled Thruxton seems kinda sacrilegious to me. Also just how much would this thing weigh?? :eek:
 

·
Registered
Joined
·
1,394 Posts
Are you thinking the engine from the new Thunderbird has been stuffed into a Thruxton? I hope that's not the case, a water cooled Thruxton seems kinda sacrilegious to me. Also just how much would this thing weigh?? :eek:

Sacreligous ?!! Please.:rolleyes:
Make the Thruxton bigger bored and weigh as much as a Street Triple ?!! You want that ? Go buy a Street Triple . Better . Fit a 675 motor in a Thruxton frame . :D

The big bore thing to be is great . Water cooled or not . The radiator might be cheesy but oh well. I'd love a 1600 Thruxton . I wanna see this thing . :hearts:
 

·
Registered
Joined
·
616 Posts
Sacreligous ?!! Please.:rolleyes:
Make the Thruxton bigger bored and weigh as much as a Street Triple ?!! You want that ? Go buy a Street Triple . Better . Fit a 675 motor in a Thruxton frame . :D

The big bore thing to be is great . Water cooled or not . The radiator might be cheesy but oh well. I'd love a 1600 Thruxton . I wanna see this thing . :hearts:
A 1600 Thruxton would be great... unless you ever needed to turn.
 

·
Registered
Joined
·
594 Posts
A 1600 Thruxton would be great... unless you ever needed to turn.
Yeah this is what I'm thinking. To me the Thruxton's biggest problem is its weight. Power is definitely #2 on the problem list, but these engines are so underpowered for what they are that increasing power is just such low hanging fruit. Bump up the CR and give us hotter cams and you're done.

In my mind, the Thrux is first and foremost a classic cafe racer, which means it's supposed to be a minimalist streetgoing vintage road racer. It's supposed to be simple, lightweight, and nimble. It's not supposed to be a drag racer, a stump puller, or a heavyweight agricultural machine. There's another brand of motorcycle that fills that niche nicely. :rolleyes:
 

·
Registered
Joined
·
616 Posts
Yeah this is what I'm thinking. To me the Thruxton's biggest problem is its weight. Power is definitely #2 on the problem list, but these engines are so underpowered for what they are that increasing power is just such low hanging fruit. Bump up the CR and give us hotter cams and you're done.

In my mind, the Thrux is first and foremost a classic cafe racer, which means it's supposed to be a minimalist streetgoing vintage road racer. It's supposed to be simple, lightweight, and nimble. It's not supposed to be a drag racer, a stump puller, or a heavyweight agricultural machine. There's another brand of motorcycle that fills that niche nicely. :rolleyes:
I don't think 75 horses at the rear wheel stock would be too much to ask for. I don't need it to be a 916 killer; and we have to keep emmissions in mind. It just needs a little more oomph -- if for no other reason than to separate from the other Bonnevilles with something more than styling. Bigger jugs and hotter cams would do that splendidly, even with EFI.

And you're spot on about the weight, but I don't have a cure that wouldn't ruin its 60's vibe, you know?
 

·
Registered
Joined
·
594 Posts
I don't think 75 horses at the rear wheel stock would be too much to ask for. I don't need it to be a 916 killer; and we have to keep emmissions in mind. It just needs a little more oomph -- if for no other reason than to separate from the other Bonnevilles with something more than styling. Bigger jugs and hotter cams would do that splendidly, even with EFI.

And you're spot on about the weight, but I don't have a cure that wouldn't ruin its 60's vibe, you know?
Yes, so many folks have shown that it's easy to boost up the power by 20hp or so. I'm not even sure that a boost in displacement is necessary, just better compression and breathing.

I disagree that weight savings would necessarily cost the historic feel. The engine is overdesigned and heavy with the balance shafts, spoked wheels are inherently heavy (esp with those monster hub castings), and the frame is built like a tank. All this adds up to about 450lbs dry weight. By comparison, a GT1000 is about 400lbs and an early SV650 is 364lbs. I'd bet that with billet hubs, a new frame and maybe some clever engine changes Triumph could get the weight below 400, but this would require some expensive development work. I suspect that the original designers concentrated so much on appearance, longevity, and "value engineering" that weight kind of fell by the wayside.
 

·
Registered
Joined
·
693 Posts
One would think with modern materials and new technology there could be some weight reduction. 1972 T120 weight in at 423 ready to ride! Take a look below:

General information
Model: Triumph T 120 R Bonneville 650
Year: 1972
Category: Classic
Rating: 72.7 out of 100. Show full rating and compare with other bikes
Engine and transmission
Displacement: 649.00 ccm (39.60 cubic inches)
Engine type: Twin
Stroke: 4
Power: 49.00 HP (35.8 kW)) @ 7200 RPM
Compression: 9.0:1
Bore x stroke: 71.0 x 82.0 mm (2.8 x 3.2 inches)
Valves per cylinder: 2
Fuel control: OHV
Cooling system: Air
Gearbox: 4-speed
Transmission type
final drive: Chain
Physical measures
Weight incl. oil, gas, etc: 192.0 kg (423.3 pounds)
Chassis and dimensions
Front tyre dimensions: 3.25-19
Rear tyre dimensions: 4.00-18
Front brakes: Expanding brake
Rear brakes: Expanding brake
Speed and acceleration
Top speed: 176.0 km/h (109.4 mph)
Other specifications
Fuel capacity: 18.00 litres (4.76 gallons)
 

·
Registered
Joined
·
3,537 Posts
One would think with modern materials and new technology there could be some weight reduction. 1972 T120 weight in at 423 ready to ride! Take a look below:

General information
Model: Triumph T 120 R Bonneville 650
Year: 1972
Category: Classic
Rating: 72.7 out of 100. Show full rating and compare with other bikes
Engine and transmission
Displacement: 649.00 ccm (39.60 cubic inches)
Engine type: Twin
Stroke: 4
Power: 49.00 HP (35.8 kW)) @ 7200 RPM
Compression: 9.0:1
Bore x stroke: 71.0 x 82.0 mm (2.8 x 3.2 inches)
Valves per cylinder: 2
Fuel control: OHV
Cooling system: Air
Gearbox: 4-speed
Transmission type
final drive: Chain
Physical measures
Weight incl. oil, gas, etc: 192.0 kg (423.3 pounds)
Chassis and dimensions
Front tyre dimensions: 3.25-19
Rear tyre dimensions: 4.00-18
Front brakes: Expanding brake
Rear brakes: Expanding brake
Speed and acceleration
Top speed: 176.0 km/h (109.4 mph)
Other specifications
Fuel capacity: 18.00 litres (4.76 gallons)
All true, Scum. However, I was taking a close scope of my motor on my '07 the other night and then thinking back to my Meriden machines - this new motor is way larger and beefier, and, it seems, so much more durable.
The weight of these new machines has not really been an issue for me, although I have heard much criticism about it. Hmmm...don't know how I'd feel about a lighter bike. Okay, I guess, but the Bonneville still seems unbulky to me.
 

·
Registered
Joined
·
616 Posts
Yes, so many folks have shown that it's easy to boost up the power by 20hp or so. I'm not even sure that a boost in displacement is necessary, just better compression and breathing.

I disagree that weight savings would necessarily cost the historic feel. The engine is overdesigned and heavy with the balance shafts, spoked wheels are inherently heavy (esp with those monster hub castings), and the frame is built like a tank. All this adds up to about 450lbs dry weight. By comparison, a GT1000 is about 400lbs and an early SV650 is 364lbs. I'd bet that with billet hubs, a new frame and maybe some clever engine changes Triumph could get the weight below 400, but this would require some expensive development work. I suspect that the original designers concentrated so much on appearance, longevity, and "value engineering" that weight kind of fell by the wayside.
I don't think you get that kind of horsepower from just compression and better breathing while still keeping the emmissions people happy is the thing.

As to peoples' comments about the weight of the old 650s, well, they WERE smaller-engined bikes. For whatever reason (rational or not), I don't think there's really a market for a 650 -- and the engine is the heaviest part of these things. At least I don't think there's an American market for something that small. Matter of fact, if you shoehorned that T-Bird 1600 into a Thruxton-esque bike, I suspect you'd sell more than you would a 650. Again -- I'm not talking about rational reasoning.

More W650s and GB500s would have been sold otherwise, right?
 

·
Registered
Joined
·
1,886 Posts
Why all this chat about the bike losing weight?

How about the riders - what do you all weigh?

I am 11 stone. Riding the Thrux today it was fast off from lights, really fast, fast enough. Nimble, manoeverable, fun.

Sat on the new Ducati 09 GT 1000 - talk about wide, high, unstable. Hardly a cafe racer.

I suspect most riders are larger now than in the 1960s.
Agreed?
So perhaps the answer lies with ourselves.

Ie go on a diet:D
 

·
Registered
Joined
·
1,394 Posts
Anyone have the link to this " Spy Photo " article ? I'm curious to see this thing. :photos::suspicious:
 
1 - 20 of 43 Posts
Top