22 replies to this topic

[oldryder]

If you are as old as I am you remember the honda 350, 360, and 450 twins, the Kaw 400, and other similar bikes. The vertical twin was popular as a cheap and relatively simple design that was somewhat underpowered and also rather buzzy at speed. for most of the past 30 years the vertical twin design was limited to bikes like the GS500 or 250 and 500 Ninja's that were considered cheap commuter or starter bikes.

the last couple of years has seen a real resurgence in new designs based on the vertical twin config. BMW, HOnda. Triumph, and Kawasaki all have new bikes that are decidely not cheapo starter bikes based on a vertical twin engine.

I know they were always cheaper to manufacture. Just wondering if there is some other significant technical consideration(s) I am missing that makes the vertical twins more acceptable than they were for the last 3 decades.

[exskibum]

I believe that new versions of the parallel twin retain several of the advantages of the design, while adding performance and comfort previously unavailable in a parallel twin.

In particular, the biggest problem with the "old" parallel twins was bad to horrendous vibration. Modern counter-balancers, better frames and more efficient combustion tame those vibes to a level far below, say, that of the bone rattling '69 BSA 650 that numbed my hands, arms and butt in the early 70s (as well as vibration from other parallel twins such as those you mentioned).

Modern technology (e.g., ignition, water cooling, fuel mapping) also enhances performance available from a compact and comparatively light weight parallel 2-cylinder power plant. Other 2 cylinder configurations generally must be larger and heavier. A parallel twin has always provided a narrow profile (heads and case), but nowadays, it also seems to allow optimized weight distribution via better placement of the center of gravity (up-down and forward-back).

In addition, a twin generally has more low end torque than a multi-cylinder engine of the same displacement, which generally makes a compact twin a better fit for motard, dual sport and/or new riders (e.g., in avoiding stalls when feathering the clutch from a stop). Combined with the lighter weight and optimized weight distribution, that probably expands the market for which the new parallel twins are ideally suited.

My 2 cents, FWIW.

[gixxerjasen]

BMW, HOnda. Triumph, and Kawasaki all have new bikes that are decidely not cheapo starter bikes based on a vertical twin engine.

Being as this is a Yamaha forum, I feel it necessary to point out a glaring oversight in your post.

[oldryder]

Excellent point, and it just helps make my case. Now they are even making "big block" twins.

[LDRydr]

The twin in my new Super Tenere has a 270-deg firing order to offset vibration and keep constant power to the rear wheel. It also allows a low and forward engine placement to keep the weight where it should be be (a side-mounted radiator helps).

This video shows more on the firing order and other features. http://www.yamaha-mo...45/0/video.aspx

[03HiYoSilver]

The twin in my new Super Tenere has a 270-deg firing order to offset vibration and keep constant power to the rear wheel. It also allows a low and forward engine placement to keep the weight where it should be be (a side-mounted radiator helps)....

Ingenius design similar to the R1 Cross-plane Crank engine:

http://www.ashonbike...oss-plane_crank

Many are complaining on the BMW's with Parallel engines about the Vibes... and they DON'T have the ability to do a TBS.

Can you do a TBS on a Super Tenere?

[wheatonFJR]

I always thought the "horizontal" twins were more popular. <wink>

Now where's that photo of them lying in bed?

[scubatech]

Americans are very nostalgic about older cars and morocycles. I am shocked at the price of these restored muscle cars. So if the design is much better it gives a lot of value to the vertical twin. Especially for those of us that can remember these bikes.

[AuburnFJR]

I always thought the "horizontal" twins were more popular. <wink>

Now where's that photo of them lying in bed?

oh yeah! BeemerDon to teh white phone please...

[madmike2]

I think exskibum outlined it "spot on".
It has more to do with the mission of the engine, so at whatever displacement level the engine/motorcycle is designed there is more through a wider rpm range of usable torque in a more narrow physical space.

[LDRydr]

Many are complaining on the BMW's with Parallel engines about the Vibes... and they DON'T have the ability to do a TBS.

Can you do a TBS on a Super Tenere?

Yes, just like the FJR. And there's a backdoor hack to adjust the CO levels on the US bikes also.

[03HiYoSilver]

Many are complaining on the BMW's with Parallel engines about the Vibes... and they DON'T have the ability to do a TBS.

Can you do a TBS on a Super Tenere?

Yes, just like the FJR. And there's a backdoor hack to adjust the CO levels on the US bikes also.

Thanks, this is good to know.

I have read on the GS' Parallel Twins, there is no adjustment and many are complaining about the VIBES.



On the Carbed 950 KTM, (Opposing Twin) there is an TBS adjustment and it is a smooth as the FJR.


Hope you are enjoying your ST10!

[beemerdons]

I always thought the "horizontal" twins were more popular. <wink>

Now where's that photo of them lying in bed?

oh yeah! BeemerDon to teh white phone please...

Fully agreed AuburnFJR and wheatonFJR, I am with you guys, I have always been much more attracted to the "horizontal" twins, I don't know what in the Hell is wrong with these other Mooks!!!

[beemerdons]

The twin in my new Super Tenere has a 270-deg firing order to offset vibration and keep constant power to the rear wheel. It also allows a low and forward engine placement to keep the weight where it should be be (a side-mounted radiator helps)....

Ingenius design similar to the R1 Cross-plane Crank engine:

http://www.ashonbike...oss-plane_crank

Many are complaining on the BMW's with Parallel engines about the Vibes... and they DON'T have the ability to do a TBS.

Can you do a TBS on a Super Tenere?

Really? I now have 18K on my 2009 BMW F650GS (800cc) Parallel Twin and it has not vibrated yet, who in the Hell is this "Many"? http://www.naggan.com/movies/CCXX2010/

[03HiYoSilver]

Really? I now have 18K on my 2009 BMW F650GS Parallel Twin and it has not vibrated yet, who in the Hell is this "Many"?

Don, Then I must apologize to you and take back this statement. This is from what I read and a ride on an older TDM I was going to buy...

Then not many and I apologize. However, I do like your other set of Twins!


Can you adjust the TBS on your Twin or this not possible?

[beemerdons]

Really? I now have 18K on my 2009 BMW F650GS Parallel Twin and it has not vibrated yet, who in the Hell is this "Many"?

Don, Then I must apologize to you and take back this statement. This is from what I read and a ride on an older TDM I was going to buy...

Then not many and I apologize. However, I do like your other set of Twins!

Can you adjust the TBS on your Twin or this not possible?

Mi "Salma Hayek" just went out of warranty, I had GO-AZ BMW of Scottsdale doing the TBS previously. But I and other Members of AZ Beemers with the F650GS and the F800GS are going to do TBS's at a Club Tech Day. If you're interested in this, I'll happily copy and mail you pages from the Haynes Manual that cover this: Chapter 9-Throttle Bodies and Chapter 10-Fuel Rail and Injectors.

This river photo is courtesy of our rushes, Tucson Joe and I had to carry his Arkie ass (yamafitter, CHRIS_D and fjrrider too!) all the way through Mexico's Copper Canyon! jes' sayin' and nuff' said!

[exskibum]

I always thought the "horizontal" twins were more popular. <wink>

Now where's that photo of them lying in bed?

oh yeah! BeemerDon to teh white phone please...

Fully agreed AuburnFJR and wheatonFJR, I am with you guys, I have always been much more attracted to the "horizontal" twins, I don't know what in the Hell is wrong with these other Mooks!!!

Attention, late-to-the-party "horizontal twin" proponents: you boobs have missed the fact that we've BEEN talking about the same twin configuration. Please note that THOSE are PARALLEL twins.

[exskibum]

duplicate deleted

[beemerdons]

I always thought the "horizontal" twins were more popular. <wink>

Now where's that photo of them lying in bed?

oh yeah! BeemerDon to teh white phone please...

Fully agreed AuburnFJR and wheatonFJR, I am with you guys, I have always been much more attracted to the "horizontal" twins, I don't know what in the Hell is wrong with these other Mooks!!!

Attention, late-to-the-party "horizontal twin" proponents: you boobs have missed the fact that we HAVE BEEN talking about the same twin configuration. Please note that THOSE are PARALLEL twins.

Oh come on now Rich, You're a Man of the World! If you use Kama Sutra Sex Positions #37, 92 and 143 (#178 will work too!): You can make them both "horizontal"!

[SacramentoMike]

Well, now the OP should go in and change the title of this thread--insert the dreaded NSFW. This would accomplish two things:

1. Avoid embarrassment from getting caught with them on your screen by your boss, wife, kids, IT administrator, pastor, rabbi, etc.

2. Alert everybody else that there's now something worth looking at in this otherwise-boring thread.