Extended Test Ride of 1125R

[mugwump58]

I got to sit on one last weekend. I was suprised how comfortable it felt, sitting still at the show mind you. Also it does look much better in person than in the magazines, not that that matters. Let's see if the horrible economy drops the price into my range. Sorry guys but I've been saving money for a time like this.

[2DFlyer]

Lost ponies?  Dunno about that...bikes use toothed flat belts, which AFAIK transmit power as efficiently as chains do (it's V-belts which lose power to friction).  Belt drives are lighter and far cleaner than chains, and there are other advantages--unfortunately, they are not as easy to change ratios on as chains, especially with the Buell "constant path length" design, and there are some strength concerns (again as compared to chains), so they are not popular with racers.

The way I understand it you can't change countershaft and sprocket ratios.  To most on the street it doesn't matter much.

[Rogue]

So is it still a testride if my friend ended up buying an 1125R?   

Well, he did end up buying a 2008 model 1125R and has so far put nearly 6k miles on his.  First off, his 2008 model needed several recall items done to it, that the selling dealer did NOT perform.  Even when we pressed the salesperson at the dealership to make sure the recall items were done, they assured us it was but later found it it was not.  I think that's grounds for a lawsuit but my friend is much more foregiving than I would have been.  We ended up taking the bike to one of the most trusted Buell dealerships in the south west, Buell of San Diego, and they actually confirmed the recall items were NOT done (simply by doing a search on the bike's VIN number).  Buell of SD performed the recall items.  These included the FI software re-map, the kickstand spring replacement, and another one for the transmission, which I can't recall at the moment.  My friend assured me that his mileage and throttle response has improved dramatically.

I recently had a chance to ride this 1125R again, this time in another favorite twisty road.  Also, the next day I was able to ride my Firebolt on the very same road and I was a bit surprised at how similar these bikes felt.  No doubt that the 1125R brakes are superior in every way to the original ZTL first seen on the Firebolt.  The power and feel is much better.  But you need to be careful not to grab a handfull too fast because the ZTL2's are very powerful.  My friend's lower mileage 1125R felt much more direct in the suspension and powertrain department than my Firebolt.  In fact, my Firebolt felt almost plush and comfortable compared to my friend's 1125R.  The 1125R does not have the Firebolt's requirement of keeping slight pressure on the bars to negotiate a long curve.  The 1125R's suspension also felt firmer.  The biggest surprise to me was the 1125R's engine has a much more direct feel to it than my Firebolt.  At idle, the Firebolt shakes more, but at revs the Thunderstorm engine feels almost uncannily smooth compared to the Helicon.  The Helicon has a direct, thumping feel to it especially when you get on the throttle or at higher RPM's.  I can't say it feels harsher because it's not harsh.  The best way for me to describe it is it has a feeling of being more directly connected to the bike, while the Firebolt's engine feels like there is some isolation fitted to it (which it does).  Of course, there is no doubt that just when the Thunderstorm 1203cc engine begins to run out of steam at 7k RPM, the Helicon engine is just about to hit its second wind and catapult the 1125R to much higher speeds. 

[Phenix_Rider]

I got to sit on one last weekend. I was suprised how comfortable it felt, sitting still at the show mind you. Also it does look much better in person than in the magazines, not that that matters. Let's see if the horrible economy drops the price into my range. Sorry guys but I've been saving money for a time like this.

I saw an '08 at the Cleveland IMS for $8k.  Though even if I had the money now, I'd wait to get an '09 that doesn't need any fixes out of the box..  

[Kootenanny]

...Also, the next day I was able to ride my Firebolt on the very same road and I was a bit surprised at how similar these bikes felt...In fact, my Firebolt felt almost plush and comfortable compared to my friend's 1125R...The best way for me to describe it is it has a feeling of being more directly connected to the bike, while the Firebolt's engine feels like there is some isolation fitted to it (which it does).

This is a quote from the editor of a Canadian motorcycle magazine, posted on their website in a thread about Buells:
"I used to race a Buell Firebolt. The biggest improvement the 1125 has over the air-cooled bike isn't the extra power of the liquid-cooled engine, it's the engine mounting itself. The 1125 engine is rigidly mounted in the frame, which greatly improves handling integrity; handling doesn't deteriorate with time requiring occasional replacement of the rubber mounts. I love those air-cooled engines; if they were counterbalanced like Harley's Twin-Cam B engines they'd be that much better."

[Rogue]

Koot, that statement is innaccurate.

Both the 1125 and XB motors are rigidly mounted.  The 1125 relies on its counterbalancers to smooth its vibrations at idle and revs.  The XB is not rubber mounted at all.  Instead, it uses a series of isolation bars to smooth the Thunderstorm's vibrations above idle.  And it works too.

However, try riding these two bikes side by side.  Guess what?  The Thunderstorm is smoother at revs.  That's right!  The Thunderstorm is smoother at revs.  The 1125's vibes are not at all severe nor would I characterize it as harsh, but it is much sharper and evident throughout its rev range compared to the Thunderstorm.     

[kevin_stevens]

Buell of SD performed the recall items.  These included the FI software re-map, the kickstand spring replacement, and another one for the transmission, which I can't recall at the moment.  My friend assured me that his mileage and throttle response has improved dramatically.

almost plush and comfortable compared to my friend's 1125R.  The 1125R does not have the Firebolt's requirement of keeping slight pressure on the bars to negotiate a long curve.  The 1125R's suspension also felt firmer.  The biggest

Hey!  When I mentioned that Firebolt tendency at Willow Springs you said it was suspension setup!

Where's "Buell of San Diego"?  Would that be the Harley dealer off Kearny Mesa?

KeS

[Rogue]

Hey!  When I mentioned that Firebolt tendency at Willow Springs you said it was suspension setup!

Where's "Buell of San Diego"?  Would that be the Harley dealer off Kearny Mesa?

KeS

You can minimize it but not completely eliminate it.  Funny thing is, it is more pronounced at low speeds than high, at least with mine.

There are two Buell dealers in SD, one in Kearny Mesa and the other at Kettener.  Both are good but the Kearny Mesa one is the best in this area.

[Kootenanny]

Koot, that statement is innaccurate.

Both the 1125 and XB motors are rigidly mounted.  The 1125 relies on its counterbalancers to smooth its vibrations at idle and revs.  The XB is not rubber mounted at all.  Instead, it uses a series of isolation bars to smooth the Thunderstorm's vibrations above idle.  And it works too.

I'm not at home right now to go out and check my bike, but I seem to recall seeing a honkin' big rubber bushing at the rear of the engine case, and I know there's one at the top of the front cylinder...as I understand it, Buell's patented "Uniplanar" engine mounting system (the series of bars you mention) connects the engine firmly to the chassis from side to side, but allows fore-aft movement (this is because the engine vibrates fore-aft but not side to side).  I'm pretty sure it's not rigidly mounted (that is, bolted directly to the frame).  I'll check and update this thread after I'm home and can take a look.

That said, I don't doubt the Firebolt feels smoother at speed--precisely because it's not rigidly mounted...

[Rogue]

Koot, you describe the Uniplanar mounting very well.  I may be confusing semantics in here but I always thought that an engine that is rigidly mounted to the frame is also a stressed member which forms part of the frame that adds stiffness.  This mounting system forms the basis of the perimeter frame that most makers use today, including the XB.  I also thought that the Uniplanar system of bars are used only to isolate the certain vibes the way you describe, but it does not suspend the engine completely on rubber, as would a rubber mounted engine would.  If the XB's Thunderstorm engine was completely rubber mounted, the frame would need farely hefty downtubes to tie and support the Perimeter frame together in order to acheive the necessary stiffness the XB has.  This would add lots of weight, and but it should also eliminate the engine vibes at idle.  The Uniplanar system currently used by Buell basically allows the Thunderstorm to be rigidly mounted to form part of the frame, hence saving lots of weight, while isolating the stronger vibrations at revs of the 45 degree V-twin.  So it gets the best of both worlds.  Smooth operation, while still retaining a lightweight perimeter frame thanks to having the engine as a stessed member. 

Note for example when H-D switched to complete rubber mounting of the Sportster engine in 2004.  They had to build in chassis rigidity with thicker tubes above and below the motor.  The result is that today's Sportster is pretty smooth at idle and revs but it gained something like 60 lbs in the process due to the chassis reinforcement needed because it lost the engine as a rigidity adding part to the frame.

[Kootenanny]

Koot, you describe the Uniplanar mounting very well.  I may be confusing semantics in here but I always thought that an engine that is rigidly mounted to the frame is also a stressed member which forms part of the frame that adds stiffness.  This mounting system forms the basis of the perimeter frame that most makers use today, including the XB.

Rogue, I'm home now, and I went out and took a close look at my bike.  You should do the same.

The engine in my Firebolt, at least, is NOT rigidly mounted  Nowhere is it directly bolted to the frame.  There are large rubber bushings supporting the engine at the top of the front cylinder and above the rear of the transmission housing; there are two short articulated links connecting the frame to the engine laterally, one at the front of the engine and one at the top of the rear cylinder, which keep the engine from moving side to side (I think these are the heart of the "Uniplanar" system).  

Using the engine as a stressed member usually means the frame can be pared down, which saves weight--as you mentioned--but Buell doesn't do that.  Instead, the XB frame uses side members with HUGE cross-sections, which makes it stiff enough all on its own.  The weird thing is that the swingarm is mounted to the rear of the transmission case, so the rubber bushings are actually between the swingarm mount and the steering head (possible because the engine is kept from twisting in the frame by the Uniplanar links).  So the Buell engine is a stressed member--it is part of the connection between the swingarm axle and the steering head--but it is NOT rigidly mounted.  

The design is weird, but it works (as you and I know)--until, of course the rubber bushings wear enough to allow any slop.  This is what the guy I was quoting above was getting at, when he talked about the handling deteriorating with time and replacing the bushings (keep in mind, he was talking about racing--he may be an editor now, but he has been a motorcycle racer and professional mechanic, too--he knows his stuff).

Check out the drawing...note the large cross-section of the frame members (keep in mind, the Buell frame only has to stretch around one cylinder, not four, so it's not as big a "hole" in the center).  It's the large cross section of the frame members that allows Buell to use the frame as a fuel tank, too.