Bonneville suspension upgrade - suggestions?

[The Other PaulG]

Every now and then I service my wife's friend's Bonnie. Taking it for a test ride after the work was completed last weekend, I really enjoyed riding it but noticed that the suspension's unpleasantly hard. Road imperfections make it straight through to your spine.

I didn't have time to play with settings, but I suspect that the (original) shocks are a bit tired by now and in need of a change. Both ends need attention, but the rear was the worst.

So... has anyone upgraded their bonnie suspension (it's an 865cc FI model) and if so what products did you use and did you see worthwhile improvements?

Cheers, Paul

 

[shuck raider]

I put Hagons with remotes on mine, plus their progressive springs on the front, big improvement

 

[AdrianS]

Lot on the net about this and no consistent answers.
I think most people who spend a lot on suspension upgrades will be happy with the improvement to justify the expense.
One or two reviews on YouTube and some impartial reviews say the upgrades aren’t as dramatic as expected.
However, the stock suspension is pretty basic and set up for a particular weight of rider and a particular road surface and probably not the pot holed roads we have now.
TEC do progressive springs with or without top adjusters. Easy( ish) to fit and not too expensive. They also do a range of rear shocks which for shocks are cheap and probably of Chinese manufacture.
The big makes also do kits but some of these are well into 4 figures.
So, you can end up spending a quarter of the bike value on shocks, and it’s only the rider who can decide the improvements are justified.

 

[The Other PaulG]

Thanks for your thoughts Adrian and yes I agree, if I ever spend on something, I'm very inclined to see improvements to justify the buying decision so it's really hard to get objective information.

Shucky, thanks for your response. Those Hagons look 'period' too, so that's an added bonus, they really suit the Bonnie's retro look.

OK I'll do some price checks and see what can be had without spending crazy money.

 

[leadfarmer]

Mine was an LC but some of this may be useful

T100 - T120 Round 2

So what'ya got then ? Bar end mirrors,sump guard and engine bars,comfort seat

www.ukgser.com

 

[The Other PaulG]

Mine was an LC but some of this may be useful

T100 - T120 Round 2

So what'ya got then ? Bar end mirrors,sump guard and engine bars,comfort seat

www.ukgser.com

Brilliant - complete with fitting instructions!

 

[chasr]

Basic Hagons + Progressives at the front. Cheap, but worked well. (T100)

 

[theoneandonly]

curved willow branch . cheap , flexible , re-do-able .

 

[Nice 'n' Fat]

I forget what I have on mine but I think they are Hagons ?

 

[The Other PaulG]

curved willow branch . cheap , flexible , re-do-able .

Can't believe I didn't think of that. It's advice like this that makes UKGSer subs such good value.

Will let you know how it goes.

 

[ShakeyGS]

curved willow branch . cheap , flexible , re-do-able .

With, or without bark?

 

[theoneandonly]

with , to show stress marks.

 

[AdrianS]

Hagon quoted me about about £430 all in for a suspension upgrade for the Speed Twin:

Progressive fork springs + thinner oil. 5w oil was suggested as the 10w as standard they thought was too thick. The oil has to be "sucked out" if you didnt want to remove the fork leg.

Rear shocks with Chrome springs. Rebound and compression damping adjustments plus 3 stage preload adjustment. These are built to order and the springs fitted to suit the riders weight. They are not rebuildable.

There is a lot of controversy over linear or progressive springs, a bit like " what engine oil"! Linear springs are what they say, even compression over a long range of compression. Great for track use and good roads. Progressive springs tend to be soft for some of the initial compression then become very firm after. Poor road surfaces are evened out and because after that, compression is very stiff, less brake dive occurs when heavy front braking. Some people say though that they get more "crashing" on the front end with progressive springs as after the initial movement, the forks stiffen up considerably, but I suppose this depends on the riders weight.

Because this is controversial, as is the whole issue of suspension upgrades, you pays your money and takes your choice.

 

[chris ponkster]

I have Hagon (2810s I think) which are fully adjustable but look like the originals (no remote res) and in the forks I have progressive springs and emulator damping valve - both have massivlt improved the pogo stick handling imo

 

[GOAT]

I had yss adjustable spring pan gas shocks on the back and Norman Hyde progressive springs on the front
I also measured static sag and then turned up some alloy bobbins to fit on top of the springs
- I also bought some fork top preload adjusters to fine tune the sag
This and a one-tooth-lower front sprocket really transformed the bike (865 carb scrambler)
Very nice ride much improved over standard