YSS Shocks V9 Bob

[Lowflying]

Took the plunge. The stockers were fine on a smooth road. Hard bumps would go right through them though. When I was younger I would’ve lived with it and not even thought about it, but, a few years ago I had a Ducati with Ohlins. Spoiled me for life. 🙄

So, today got these YSS shocks installed by my local bike shop. Been using this shop for years, trust them, and they like me because I always pick up my bike right away and pay up, often in cash. They tell me when I don’t really need to get something done, or if the job is not up their alley.

They set up the sag and I’ve got the compression and rebound right in the middle, to start with.

Initial impression. Great. Controlled and smooth. Still feel a bump but it’s not a jolt through the spine. Happy.😎





The fork is good enough for me. For now anyway.

[blu guzz]

When I got my first Ohlins, i was surprised at how firm they felt.  But, then hit the first teeth rattling bump (intentionally to test) and glory be, it didn't disappear by any means, but my teeth didn't rattle either and I agree with you that they are addicting, but expensive.

[SIR REAL ED]

Did you get the same length as the stock shock?

I have often thought that looks wise, 2" longer shocks would be an improvement.

[Lowflying]

Did you get the same length as the stock shock?

I have often thought that looks wise, 2" longer shocks would be an improvement.

From the description of the shock, the length is adjustable. But I believe the mechanic left the length as standard, although I didn’t specifically ask the question. I thought they might have been a bit longer but I’ve looked at before and after pics and it seems the same to me. Maybe longer might handle better, but I don’t think it would look better IMO.

As blu guzz said, as I rode away I was thinking they felt a bit firm, but going out of my way to hit some bumps I discovered that they felt heaps more compliant. No jolts through the backside. Result! 

[faffi]

I think adding two inches would cause a lot of stress on the U-joints, and also change the geometry quite substantially. It would bring some much-needed cornering clearance, though.

[Frenchfrog]

I believe you are 100 % on the money faffi.
Shock length has a direct effect on universal joint geometry too.mess with that beyond a very small margin and you are asking for trouble and not of any minor kind either. A UJ breakdown on a small block is extremely dangerous as it nearly always takes out the back of the gear box and swinging arm mounting points too.That might conclude in hospital or morgue trips instead of a road trip.

[Alfetta]

this is my largest complaint i have with my bike, I am on a V7 but the V9, i suspect, has a similar problem.
I have looks at changing shocks, and have spent many hours thinking about this issue.
in a nutshell, i don't think there is sufficient stroke to cope with sharp edge impacts while maintaining a supple ride.

I don't want to change the geometry of the bike, thus I have come to the belief that these bikes need some form of progressive link (much like a dirt bike) so the current travel of the swingarm stays the same, but the shock stroke is increased by a factor of 2
This would allow greater flexibility in comp and rebound dampening coupled with soft settings for initial travel, firmer values as the stroke gets consumed.

However, due to the lower fixing location of the shocks being very different on each side of the bike and the proximity of the gear box to the swing arm pivot, creates some form of linkage problematic, quickly..

So I'm off to the store for some padded panties...

[faffi]

If you up the travel, the U-joints will again be taxed more, whether the extra travel take place above and/or below the horizontal. A more progressive action with twin shocks through linkages have been done (was it on the Honda Big One?), not so much to gain wheel travel as to get progressive damping action. Progressive springs can mimic linkages, but only (AFAIK) linkages can alter damping along with travel.

BTW, most motorcycles have a regressive action, making damping and springing softer as the wheel travels up and the suspension is compressed. This is due to most shocks being inclined forward. The original Honda XL250S and 500s had this feature to the extreme. Again, progressive springs can compensate, but the damping is not catered for.

As to the Guzzis and their rear suspension; the lack of comfort and control stems primarily from sub-standard shock absorbers, but the bikes could do well with 20mm more rear wheel travel, and increase the U-joints should be able to cope with if the shocks are of good quality.

[SIR REAL ED]

I think adding two inches would cause a lot of stress on the U-joints, and also change the geometry quite substantially. It would bring some much-needed cornering clearance, though.

That is definitely a good thing to consider.  If I were going to put longer shocks on a shaft drive bike I owned, I would want to disassemble the driveshaft and take a lot of measurements.  Angle of hardstopage is a great thing to know.

If the bike were new, it would be a great opportunity to see how well things are greased.

[SIR REAL ED]

this is my largest complaint i have with my bike, I am on a V7 but the V9, i suspect, has a similar problem.
I have looks at changing shocks, and have spent many hours thinking about this issue.
in a nutshell, i don't think there is sufficient stroke to cope with sharp edge impacts while maintaining a supple ride.

I don't want to change the geometry of the bike, thus I have come to the belief that these bikes need some form of progressive link (much like a dirt bike) so the current travel of the swingarm stays the same, but the shock stroke is increased by a factor of 2
This would allow greater flexibility in comp and rebound dampening coupled with soft settings for initial travel, firmer values as the stroke gets consumed.

However, due to the lower fixing location of the shocks being very different on each side of the bike and the proximity of the gear box to the swing arm pivot, creates some form of linkage problematic, quickly..

So I'm off to the store for some padded panties...

Good points.  Street legal dual sport bikes with 8+" of suspension travel absolutely ruin you for riding a street bike on anything but smooth roads.

I suspect due to hardstops in the swingarm pivot, not a lot of additional suspension travel is available.

Anytime the u-joints are not in a straight line, wear will be increased.

Botox shots in the butt cheeks may be a viable alternative.  Assuming your pants still fit....

[faffi]

BMW now consider shafts to be a wear item, like chain and sprockets, and give replacement intervals between 40 and 60,000 km (25 and 40k miles). I believe on new models, the owner must pay, whereas on older bikes it is free of charge. But I can be mistaken.

[Frenchfrog]

That was the same for the Sport 1100 series which had exposed UJ's too...can't remember offhand what the renewal intervals were but it was rather low !!!

[SIR REAL ED]

BMW now consider shafts to be a wear item, like chain and sprockets, and give replacement intervals between 40 and 60,000 km (25 and 40k miles). I believe on new models, the owner must pay, whereas on older bikes it is free of charge. But I can be mistaken.

Someone else here, who has owned a couple BMW GS models posted the same.  Perhaps because of the increased wheel travel.

Drive shafts are a wear item!  That's an unthinkable concept to us old farts who remember the 1970's when drive chains were crap, and we jumped at the chance to buy Yamaha XS models and Suzuki GS models with shaft drive.

Oh how we used to brag about our shaft drive bikes!!!!

So clean and zero maintenance!!!

[Alfetta]

Increasing the travel in the rear will change to geometry of the front. changing rake angle and trail values. So if you do one end you should do the other, or live with a twitchy sticky front.

Personally I like the handling and feel of my 7,  just hate the harshness in the back. so i still think that the best solution would be a link system that would maintain the current position and travel at the back (so no front change required, and nothing new required of the u-joints) but increasing the stroke travel of the shock to allow for more oil displacement control and spring rate variation....

[Moparnut72]

That is strange, what has happened to BMW. I had a short framed R75/5 which had 8" of travel at both ends. I sold it with just a few miles short of 100,000 miles. I had no problems with the drive shaft or Ujoint. The drive shaft ran in an oil bath, the bike had four oil reservoirs, the engine, trans, drive shaft housing and final drive. I replaced it with an R90/6, both good bikes but I would doubtfully own another BMW.
kk 

[faffi]

Just to be pedantic, the old BMW air heads had 8 inches of front wheel travel, as you mention, but "only" 5 inches in the rear. Which was still plenty more than the opposition offered.

[Moparnut72]

You are right I misspoke. I had one of the very first R75's in the country and I was going on memory, that was a long time ago. It rode quite well, even better with upgraded front springs and Fox Shocks. The front springs because I had a full Avon fairing on the bike.
kk