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Discussion Starter · #21 ·
And loss of reliability.

About 1 hp (+-) per 10cc of engine displacement is pretty close to the 'standard' for reliability.
310 GS = 32 hp or so. 390 KTM = 41 hp or so. FJR 1300 = 140 hp or so. etc etc.
On the other hand... professional 250cc Motocross with 48 hp = rebuild every race for factory teams.
GP bikes... 1000 cc engines.... 300 hp. They have 7 engines to get through a racing season.
That is one theory.
Another is 1 BHP per cubic inch. This was first achieved in a mass produced engine ( disputably, but specifically promoted, and generally accepted to be ) with GM's 283 cu ins V8 with Rochester Ram-Jet fuel injection, matched with a manual transmission. Developed by Zora Arkus Duntov under GM's chief engineer Ed Cole, with help from John Dulza, the Ram Jet was launched as a $550 option ( in regular and high power versions ) on 1957 Chevys, including the 150, 210, Del Rey, Nomad, Bel Air, and Corvette models.
Given the comparatively light weight of these cars, they posed daunting potential racers. Campaigned under SEDCO ( which employed Smokey Yunick, and spawned the legenday Skunk works in 1958 ), the famous Black Widow 150 swept the field in 1957. So successful was the campaign that the NHRA banned fuel injected engines during that same season.
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Wait, I've seen that car somewhere before..... :)
 

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Hi, There has been a lot of talk here. The simple fact is if you are red lining your bike a lot then it's going to fail in some way or other EARLIER. What is earlier?.....who knows. But go for it if it spins your wheels. I used to red line a Mark 1 Cortina GT in my youth, it was fun but didn't spoil the fun by making that angry noise & vibrating like hell, the latter which the 310 does over 6000RPM.
 

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PS/I find the concept of needing to sell as soon as the warranty expires a bit sad given the substantial loss in up-trading. Also the notion that the 310 is only an around town machine or shouldn't be ridden in a straight line a constant revs for a while sad also. Just ride the thing & enjoy it (ie constant red lining aside!!).
 

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Discussion Starter · #25 ·
Hi, There has been a lot of talk here. The simple fact is if you are red lining your bike a lot then it's going to fail in some way or other EARLIER. What is earlier?.....who knows. But go for it if it spins your wheels. I used to red line a Mark 1 Cortina GT in my youth, it was fun but didn't spoil the fun by making that angry noise & vibrating like hell, the latter which the 310 does over 6000RPM.
Hi Mike. Welcome to the new thread inspired by your own on exhausts. In response to your points:
'Fail earlier'
Like anything you use harder, it will fail earlier. Only experience will tell what that means with the GS.
However, the fact remains that this bike was designed to run up to the red line.
'Vibrate like hell'
That is an emotive turn of phrase, and for my GS inapropriate.
Does it vibrate- Sure ! But it's a single, or 'Thumper' ! By their very nature, single cylinder engines are not smooth running in the way that your inline 4 cylinder Cortina was.
See point 2 below, on this older thread
'Angry noise'
Again, an emotive description. Classically, this is a sign of coming 'into the power band' or 'on cam'. It is an indication of reaching the peak power of the engine. To many, it is considered a desirable thing- especially to racers. It is the sign that you are 'in the right place' in the rev band for maximum power. To maximise performance, you want to use the gears to keep within that range of rev's. If you enjoy any form of motor sport, half of the fun is hearing the vehicles 'roaring' around the track.

Hi,
As a rider for over 20 years, I think that you already have 2 very good replies:
But maybe I can still contribute something, since you state that you are a new rider, and there is a bit more to the total picture.
1) Running in
You should run the bike in, as specified in the manual.
This will extend the life of the motor, but will have little effect on it's overall feel. ( I actually did 1,000 miles, not just the specified 750 )
2) This bike is a single cylinder.
This format is inherently unbalanced, since there is only the weight of a single piston being thrown up and down inside the motor- up, stop, down, stop, back up.
Even with balancing weights on the crank to counteract the forces created, it will never be as smooth as an inline twin cylinder, or triple, or the most balanced of all inlines, a
four. In these formats the pistons are timed to rotate in an order to help smooth out vibration by counteracting the weight of one piston with the weight of another.
Other options, like BMW's famous 'Boxer' twin engine have 2 'opposing' cylinders. One cylinder comes out of one side of the engine, and the other on the other side.
The weight of one piston is counteracted by the opposing piston on the other side- Inherently smoother than all the above.
3) High revving engines
As the quote above, with modern lubricants and technology, engines are designed to rev high. It's not a problem !
So, I really think the concept of 'strain' at only halfway through the rev. band is misleading.
The bike is NOT 'straining', it is vibrating ( sure ), and getting nearer to the higher level of power output ( 'coming on cam' ),
That's not doing the bike any harm at all. In fact, it's exhibiting both the designed performance ( more power at higher rev.s ) and the limitations of the motor's format. ( single
cylinder at faster revolutions = more vibration )
I grew up riding 2 stroke 'screamers', which were all about maximum BHP in very narrow power bands at the very top of the rev. range.
That simply meant high rev.s or zero power. Check out reviews of the Kawasaki Mach III H1 from the 70's for the most extreme illustration: 2 choices- power off, power on !
The red line is your guide for the limits of the engine, and as a fail-safe, there is an automatic rev. limiter which just cuts the engine if you go over it.
But that says nothing about your comfort !
If you don't like the feel of the high rev.s, you'll learn how to avoid them.
4) Gears
Gears are primarily designed to maximise the power of the engine to obtain the highest speed possible.
Anyone using a pedal bike knows that to try to start off in top gear is near impossible.
Likewise, you cannot possibly pedal fast enough in a low gear to get to the same speed you can in top gear.
Now, transpose this to the motorcycle, thinking of what you asking your motor to do in each gear.
Now, question: Why do you want to 'cruise' in a low gear ? What are you trying to achieve ?
It seems to be a bit like looking through the wrong end of a telescope. You can do it, sure. But, why would you ?..
If you want the bike to feel 'lazy', choose a higher gear. Less rev.s, less vibration, but less power/slower reactions to the throttle.
Lower gear at the same speed means more rev.s, and it'll feel 'busy' !

I hope some of the above helps.
 

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Discussion Starter · #26 ·
PS/I find the concept of needing to sell as soon as the warranty expires a bit sad given the substantial loss in up-trading. Also the notion that the 310 is only an around town machine or shouldn't be ridden in a straight line a constant revs for a while sad also. Just ride the thing & enjoy it (ie constant red lining aside!!).
I couldn;t agree more ! But this is only one person's opinion. I see many of these bikes with very low mileage, but I also see some people who have done some serious travel on them. Personally, I have almost done 12,000 miles so far, ( while consistantly using rev.s all the way up to the red line ) with no serious issues. I am coming up to the end of warranty, and have no intensions to sell because it's coming to it's end. That said, I have also looked after the bike. I ran it in for 1,000 miles ( not just the stipulated 750 ), and had it serviced slightly MORE often that the manual requires. But I am sure that you can search and find threads from real long distance riders that would give more extensive info. than this. Good luck, and enjoy !
(y):)
 

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I'm not sure who is being referred to as a new rider. Personally I'm 80 & have been riding for 65 years. Of course you can red line it, that's what the red line is for. My point is red line it consistently & unnecessarily & it will fail earlier. But you younger guys are used to over square piston bikes & high revs. Go for it! I disagree about the vibration, it's bad over 6000 rpm. And yes it's a thumper.
 

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I'm not sure who is being referred to as a new rider. Personally I'm 80 & have been riding for 65 years. Of course you can red line it, that's what the red line is for. My point is red line it consistently & unnecessarily & it will fail earlier. But you younger guys are used to over square piston bikes & high revs. Go for it! I disagree about the vibration, it's bad over 6000 rpm. And yes it's a thumper.
PS/The Cortina GT was designed for red lining with each car having individual balanced pistons, con rods & flywheel. Has the 310?? Also as has been mentioned race bikes have their engines regularly stripped & rebuilt to blue print specs, ie toleranced out to the max allowable.
 

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Discussion Starter · #29 · (Edited)
I'm not sure who is being referred to as a new rider. Personally I'm 80 & have been riding for 65 years. Of course you can red line it, that's what the red line is for. My point is red line it consistently & unnecessarily & it will fail earlier. But you younger guys are used to over square piston bikes & high revs. Go for it! I disagree about the vibration, it's bad over 6000 rpm. And yes it's a thumper.
Hi Mike.
Please check above, the reference to a 'new rider' is within a quote from an old thread. It wasn't aimed at you. Besides, as I put right at the top, this thread is primarily aimed at the novice. It was not addressed as a reply directly to your good self. The goal is to help disseminate knowledge generally.
Vibes- It's subjective, and maybe my example is smoother than yours- Who knows. But, compared to vintage British iron, my baby doesn't register on the Richter scale at all ! It's just a noticeable buzz.
Agreed re the vibration-killing balancing on your Cortina- But beyond a crank/flywheel counter weight, how do you balance a single ? However, isn't this now reaching the realm of the purely academic ?
If the vibration on your GS is so intrusive, perhaps you should get your dealer to take a look....
 

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3) That if you are considering spending money on performance products, if you never use more than 6,000 RPM, you could probably find a better home for it elsewhere. But it's YOUR choice.

ref quote above:
While I get the inference above, many forget the fact that the Akrapovic exhaust provides a significant savings in weight compared to the standard exhaust. Weight savings impacts acceleration and deceleration regardless of RPM settings and also helps when you have to pick up your bike should be unfortunate enough to have dropped it. It also affects how snappy the bike is coming back up from a lean.
Cheers all!
 

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Here's why the 310 is as smooth as it is: Heavy well engineered counterweights. This is one of the reasons I don't mind that the G310GS is heavier than many other 300cc bikes. I've had nothing but in-line three and four cylinder bikes since 1987. The first time I rode my 310GS, I was shocked at how smooth it was.

Interesting side note: Per below, the 2018 thru 2022 all have the same crankshaft part number. At $967, I hope I never need one.

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Discussion Starter · #32 ·
3) That if you are considering spending money on performance products, if you never use more than 6,000 RPM, you could probably find a better home for it elsewhere. But it's YOUR choice.

ref quote above:
While I get the inference above, many forget the fact that the Akrapovic exhaust provides a significant savings in weight compared to the standard exhaust. Weight savings impacts acceleration and deceleration regardless of RPM settings and also helps when you have to pick up your bike should be unfortunate enough to have dropped it. It also affects how snappy the bike is coming back up from a lean.
Cheers all!
Weight reduction is always part of the performance equation, and often forgotten, as you rightly say. That includes the rider and all his kit !!! :giggle:
The Chrysler racing team of the 60's started to dip all the body panels of their cars in acid to reduce the thickness of the metal for that reason, and I believe that it was an F1 team that was once disqualified for using aluminum foil ( for cooking ) as a 'metal firewall' on their car !
 

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Today I rode the snowflake on parts of the Rattler (209 south of Hot Springs NC) and US 276 across the (closed) Blue Ridge Parkway between Waynesville NC and Brevard NC, but most of the day was spent well below snowflake revs in the Martha Sundquist State Forest in TN. On the other hand, we did see some actual snow patches at the higher elevations (4000 feet) and the melt off made for a slippery and messy ride. P.S. Headlight guard and turn signals are clean because I cleaned them during a break after we were back on pavement. P.P.S As I was typing this, I noticed and confirmed the rip in the left side of the rider's seat area. I caught a 2-1/2" diameter branch at one point and it jumped up and poked the back of left thigh; I guess it ripped the seat at the same time. 馃槶

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Discussion Starter · #36 ·
Today I rode the snowflake on parts of the Rattler (209 south of Hot Springs NC) and US 276 across the (closed) Blue Ridge Parkway between Waynesville NC and Brevard NC, but most of the day was spent well below snowflake revs in the Martha Sundquist State Forest in TN. On the other hand, we did see some actual snow patches at the higher elevations (4000 feet) and the melt off made for a slippery and messy ride. P.S. Headlight guard and turn signals are clean because I cleaned them during a break after we were back on pavement. P.P.S As I was typing this, I noticed and confirmed the rip in the left side of the rider's seat area. I caught a 2-1/2" diameter branch at one point and it jumped up and poked the back of left thigh; I guess it ripped the seat at the same time. 馃槶

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Back, and in high style, JerryG !(y)
 

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Question asked by @Mike Stockwell on the former thread where this discussion started:
"Ask yourself how long can the bike rev at the red line before .......what?......seizing or piston thru the side or a thrown con rod."

The general answer to this question is that manufacturers determine redline by testing. However, testing always has use-cases. This implies that the G310GS redline should be sustainable for those use cases. Let's hope BMW/TVS got those right.

That said...

I was recently informed, by a unimpeachable source with first hand knowledge and lots of experience, about three G310GS engines that failed in use.

The first two were when the G310GS engines "ate a valve", both at just under 30,000 miles. Knowing the source, I'm sure the engines were well exercised during those 30,000 miles. The source also told me that, despite being out of warranty, BMW replaced both engines. I queried for additional info on the circumstances, but nothing further has been offered.

The third G310GS engine failure was one of the above replacement engines; the crankshaft "became deranged" at about 3,500 miles, failing so badly that it cracked the engine case. BMW replaced this engine because it was still under the two year replacement parts warranty from the first replacement.

The source also told me that they now ride these G310GS "mostly locally...and not to tour on like we have".

Re the valve failures: Because of this, I'm not going to be skipping valve adjustments on my G310GS. I might even go the other way by increasing their frequency from once every 12,000 miles to once every 6,000 miles. Purely by coincidence, I have scheduled my 12,000 service for next week; this is early as I only have 10,577 miles. I'm doing this service early only because my dealer is moving to a new location (closer to me - yeah!) and might not be able to do the service when I expect to be at 12,000 miles. Depending on what they report about my valve clearances from that service, I might decide to increase the valve inspections/adjustments from every 12,000 miles to every 6,000 miles.

Re the crankshaft failure: I attribute this to a "bad part", i.e. a random failure for which nothing can be done to avoid or even watch out for.

Re their local/tour decision: I have 10,577 miles on my G310GS with no problems. Given the above information, my plan is to minimize straight flat boring long distance high RPM runs. Two examples: I will be trailering my G310GS from NC to California to do the CABDR and attend the Death Valley Noobs Rally in March this year, but I will ride my G310GS to and from NC when I do the Mid-Atlantic BDR, PA Wilds BDR-X, and BMW National Rally in Richmond VA in May/June, all in one trip.

Re my warranty: Given these three engine failures, I intend to max out use of my G310GS during it's three-year, 36,000 mile, warranty. After that, we'll see.
If I recall correctly, the TVS manual has valve checks at 6000 miles.


Edit: confirmed. TVS workshop manual says inspect & adjust every 10km
 

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My BMW manual says "Check valve clearance" every 12,000 miles (see first pic below) and I just had my 12,000 mile service completed early at 10,770 because my dealer will be in the middle of a move when I hit 12,000 miles and the bike and I will be on a trip right after that. The valve clearance results are in second pic below and stated here:

INTAKE VALVES: 0.15MM AND 0.13MM. (SPEC: 0.11MM - 0.20MM)
EXHAUST VALVES; 0.28MM AND 0.30MM (SPEC: 0.26MM - 0.35MM)

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I鈥檇 say Jerry鈥檚 experience is like many with the new tech valve train. Technically he鈥檚 within specs and ready to roll. Not an uncommon experience anymore. Low wear from almost frictionless moving parts. This is one of the many reasons the 310 is a free revving unit and along with counter balancers is why 10,000 rpm鈥檚 is not a big deal, in fact it鈥檚 optimal By design. These motors may experience very long life鈥檚 which would correlate with low emission tech, DLC etc. Lots of bikes rev even higher like the Kawasaki Versys or there鈥檚 old school bikes like the Honda GL 500. Vibrations are what kill high rpm engines. By reducing imbalances higher rpm鈥檚 are sustainable. At the rate motorbike tech is advancing and changing, I find it hard to believe that one would want to continue to own a 310 after three years, there will be something much better out. Could you imagine half the weight and double the power?鈥︹.and affordable.
 

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I find it hard to believe that one would want to continue to own a 310 after three years, there will be something much better out. Could you imagine half the weight and double the power?鈥︹.and affordable.
Now, now, I think those last couple sentences belong on the rumor/wishful thinking thread. 310s forever!馃槣
 
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