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breakaway
12th April 2014, 09:00
I've spotted a bike I want to buy but I am concerned about the fact that it's been lowered.

Personally I'd never consider lowering a bike at all because of potential concerns regarding what would happen to the suspension geometry etc, but this one has had it done.

What do I need to look out for in this case?

A quick google search shows that there are multiple ways to do this, one being taking sag out of the suspension and another being using lowering links. Then there's many forum posts that came up in my search of people with differing opinions. One says it's all good, the other says it makes the bike feel really unstable at low speeds.

I'm interested in opinions from experts and people who have been through the process -- any insight appreciated. My first port of call would be to have it reversed and re-set at the stock height.

george formby
12th April 2014, 09:03
My girlfriends trailie has lowering links (dog bones) & the yokes dropped on the forks. No issues whatsoever.

shafty
12th April 2014, 09:05
George has it right

tigertim20
12th April 2014, 09:16
it depends on the bike. Ive ridden one or two that were lowered and were fine, others that were, quite frankly, fuckin dangerous.

if youre going to reset it to stock anyway, what does it matter provided everything else checks out?

haydes55
12th April 2014, 09:23
Give it a test ride. If you like it you like it

Oakie
12th April 2014, 09:26
The previous owner of my bike had it lowered for his wife and did it properly with a new link. I wanted it reinstated to full height for me which he did. Handles fine. Still got my mechanic to look at it later just for my peace of mind and he was happy with it.

Lowering per se isn't a bad thing as long as it was done (and reversed) in a competent manner.

Wingnut
12th April 2014, 09:28
A little off topic but,

When I had my M109 I lowered it cause I thought it looked cool. It sucked.... Cornering became a grinding issue. Mind you, that was on a big ass whale of a cruiser.. Don't know what the fuck I was thinking!!!:no:

skippa1
12th April 2014, 11:42
A little off topic but,

When I had my M109 I lowered it cause I thought it looked cool. It sucked.... Cornering became a grinding issue. Mind you, that was on a big ass whale of a cruiser.. Don't know what the fuck I was thinking!!!:no:
Those things don't have any ground clearance to start with.

now back on topic

Oscar
12th April 2014, 12:01
My girlfriends trailie has lowering links (dog bones) & the yokes dropped on the forks. No issues whatsoever.

You should really change the shock spring.
I've seen bikes lowered with dogbones where the spring is compressed past tolerance.

SMOKEU
12th April 2014, 12:49
Just make sure it's not too low that you run out of lean mid corner.

Wingnut
12th April 2014, 13:14
Those things don't have any ground clearance to start with.

now back on topic

Agreed....

F5 Dave
12th April 2014, 13:18
many people sell lowering links. Most of them are Ill conceived. Find out how it's been done and if reversible. You can walk away.

Robert Taylor
12th April 2014, 13:36
George has it right

Bollocks. Most lowering links are made by companies who never reply if you ask them for the revised linkage curve graph and if you ask them if the wheel / tyre is still going to clear the inner mudguard at full compression. Its because they've made the links just to make money without concern of any negative side affects. Fancy anodising, packaging and claims fools the great buying public into thinking they are actually credible. Its also very sad that a lot of dealer personnel go along with this travesty.

Sometimes you get lucky but it really annoys me when people make blanket statements on forums on the basis of their extremely limited sampling range.

The only way to lower a bike properly is to shorten the suspension ( professionally ) and making compensatory spring and valving adjustments to account for the more progressive part of the linkage curve ratio happening a little sooner.

Like I said sometimes you get lucky but we see many lowering jobs that are just terrible

HenryDorsetCase
12th April 2014, 13:51
The other thing is if the shock is lowered what has happened in the front? Just push the forks through the clamps au?

My Street Triple R has a TTX36 in it which is slightly shorter than stock (Thanks Robert) and I have pushed the forks up a little. It dropped the seat a little. A very little.

I am actually a Hobbit so it helped. But I (fortuitously?) ripped the stock seat cover on my bike. When I get it re-covered I am going to get the foam re-contoured: I reckon that will make the most difference.

And lowering a street bike is only really an advantage a bit of the time while the thing is stopped or moving slowly.

If I want a dirt bike I have to stick with pre 1970 technology because the seats are low. BSA B44!

george formby
12th April 2014, 14:03
You should really change the shock spring.
I've seen bikes lowered with dogbones where the spring is compressed past tolerance.

Been checked & set up for her. All good. TBH the dog bones did not lower it much.

HenryDorsetCase
12th April 2014, 14:04
Just make sure it's not too low that you run out of lean mid corner.

I test roda a Harley Sportster and took it on my test loop that I test ride all bikes on: up and over Dyers, out to the Wheatsheaf then over Gebbies and back: it gives a good range of conditions to assess the bike. On the way up to the Kiwi at a very moderate pace I was dragging bits of the bike on the ground where I have never hit anything before (or since) on any bike I have ever ridden. It was comedy. Fine going straight but if you are used to anything else.... I have only ever ridden two cruisers but the compromise for Hobbit seat height is very apparent even at a nana pace....

george formby
12th April 2014, 14:11
Bollocks. Most lowering links are made by companies who never reply if you ask them for the revised linkage curve graph and if you ask them if the wheel / tyre is still going to clear the inner mudguard at full compression. Its because they've made the links just to make money without concern of any negative side affects. Fancy anodising, packaging and claims fools the great buying public into thinking they are actually credible. Its also very sad that a lot of dealer personnel go along with this travesty.

Sometimes you get lucky but it really annoys me when people make blanket statements on forums on the basis of their extremely limited sampling range.

The only way to lower a bike properly is to shorten the suspension ( professionally ) and making compensatory spring and valving adjustments to account for the more progressive part of the linkage curve ratio happening a little sooner.

Like I said sometimes you get lucky but we see many lowering jobs that are just terrible

Must admit my quest for further info on the effect of using the lowering links, from Lust Racing, UK, was met by a wall of silence.
Took a punt that a softly sprung, light, trailie would not be as upset with lowering links as it would being dropped because of height. Compared to the OE links, assuming they are OE, there was barely a couple mm difference in centres.
In my ignorance I have not noticed any issues or shock problems.
Any hoo, live & learn.
Thanks for yer input.

shafty
12th April 2014, 14:12
Bollocks. Most lowering links are made by companies who never reply if you ask them for the revised linkage curve graph and if you ask them if the wheel / tyre is still going to clear the inner mudguard at full compression. Its because they've made the links just to make money without concern of any negative side affects. Fancy anodising, packaging and claims fools the great buying public into thinking they are actually credible. Its also very sad that a lot of dealer personnel go along with this travesty.

Sometimes you get lucky but it really annoys me when people make blanket statements on forums on the basis of their extremely limited sampling range.

The only way to lower a bike properly is to shorten the suspension ( professionally ) and making compensatory spring and valving adjustments to account for the more progressive part of the linkage curve ratio happening a little sooner.

Like I said sometimes you get lucky but we see many lowering jobs that are just terrible

I was replying from the perspective that the bike was to be reinstated

haydes55
12th April 2014, 14:15
I test roda a Harley Sportster and took it on my test loop that I test ride all bikes on: up and over Dyers, out to the Wheatsheaf then over Gebbies and back: it gives a good range of conditions to assess the bike. On the way up to the Kiwi at a very moderate pace I was dragging bits of the bike on the ground where I have never hit anything before (or since) on any bike I have ever ridden. It was comedy. Fine going straight but if you are used to anything else.... I have only ever ridden two cruisers but the compromise for Hobbit seat height is very apparent even at a nana pace....


The good news is, if you forget to put the side stand out on a Harley, it will just rest on the foot pegs anyway.

tigertim20
12th April 2014, 15:26
Im not sure why everyone immediaely fucks with the suspension.
careful selection of available tyres based on their contour, along with modifying the seat foam, and even adding slightly thicker sole to ones riding boots makes a fairly subtantial difference when all added up, without having nearly as drastic potential effects on handling.

Robert Taylor
12th April 2014, 15:27
I was replying from the perspective that the bike was to be reinstated

Ok, fair call.

This whole issue of lowering is a much bigger can of worms than people realise, including dealers!

Robert Taylor
12th April 2014, 15:35
I test roda a Harley Sportster and took it on my test loop that I test ride all bikes on: up and over Dyers, out to the Wheatsheaf then over Gebbies and back: it gives a good range of conditions to assess the bike. On the way up to the Kiwi at a very moderate pace I was dragging bits of the bike on the ground where I have never hit anything before (or since) on any bike I have ever ridden. It was comedy. Fine going straight but if you are used to anything else.... I have only ever ridden two cruisers but the compromise for Hobbit seat height is very apparent even at a nana pace....

In the case of such bikes ( also most Japanese and nasty mainland Asian twin shock bikes ) it is not neccessarily and SOLELY about raising the ride height to stop constant scaping / grounding. Most of the mass produced oem twin shocks and also the cheap and less than cheerful aftermarket offerings are of twin tube construction with a very restrictive check plate passage at the bottom of the inner tube. Such shocks are not pressurised. So the more undulating and bumpy the road is the more and more the shocks cavitate. Felt to the rider as constant wallowing and grounding. Because when cavitation happens there is no damping control so the dynamic ride height control suffers. Fitting some decent quality and gas pressurised aftermarket shocks at exactly the same length will on its own account deliver higher ride height, dynamically.

Katiepie
12th April 2014, 22:34
I lowered my R6 with dog links, and had the front dropped on the forks the keep it level. I know very little about the effects of this or exactly how it has been done (yes, I should know), but personally love how it handles. But I don't ride the bike anywhere even close to it's potential so for me it works just fine. Anyone else however that rides me bike gets off saying it all feels very strange. I guess I've only ever ridden it like that so unsure of what "normal" feels like.

But yes, ground clearance can become an issue - as I found out last week for the first time. Just now know it's "lean limits".

Robert Taylor
13th April 2014, 10:48
I lowered my R6 with dog links, and had the front dropped on the forks the keep it level. I know very little about the effects of this or exactly how it has been done (yes, I should know), but personally love how it handles. But I don't ride the bike anywhere even close to it's potential so for me it works just fine. Anyone else however that rides me bike gets off saying it all feels very strange. I guess I've only ever ridden it like that so unsure of what "normal" feels like.

But yes, ground clearance can become an issue - as I found out last week for the first time. Just now know it's "lean limits".

To not put too fine a point on it the people making these lowering dogbones also know very little about any possible negative side effects, nor do they actually care. We have had more than a few bikes through with these ''land of milk and honey'' dogbones and the stability and control has left a lot to desire. Sometimes as I said you get lucky but its akin to russian roulette. There are a lot of people making money out of selling pretty mediocre product.

jellywrestler
13th April 2014, 11:28
The only way to lower a bike properly is to shorten the suspension ( professionally ) and making compensatory spring and valving adjustments to account for the more progressive part of the linkage curve ratio happening a little sooner.

or letting 20 psi out of each tyre...

Robert Taylor
13th April 2014, 11:56
or letting 20 psi out of each tyre...

Or in your case letting 20psi out of your blow up tranny doll!

jellywrestler
13th April 2014, 12:32
Or in your case letting 20psi out of your blow up tranny doll!

Mines been filled with polystyrene balls after the incident in Stratford two years ago, had to do it twice. The first time they all squeaked so I took them out and coated each one in vaseline before putting them back in, you can imagine how hard it was to reinsert them with them all sticking to my fingers.

Robert Taylor
13th April 2014, 13:11
Mines been filled with polystyrene balls after the incident in Stratford two years ago, had to do it twice. The first time they all squeaked so I took them out and coated each one in vaseline before putting them back in, you can imagine how hard it was to reinsert them with them all sticking to my fingers.

Stratford fortunately has adequate demographic disposition to New Plymouth.