Any advice on Bonneville suspension upgrade please ?

Greetings Triumph people. I'm an 'oldie' that returned to biking about 10 years ago, and I have just joined this Forum as I've recently bought a 2015 A3 Bonneville (ex demo, only 6 months old, silver paintwork - wow !). Apart from being reminded of motorcycles of my youth, I'm just loving the relaxed riding style the character of the Bonnie engenders, not to mention the beautiful burble eminating from the reverse-cone exhausts.
I'm very much aware that the Bonnie suspension has design limitations on it's effectiveness compared to machines of more modern design, but general trawling on the 'web' indicates that aftermarket upgrades can make a noticeable improvement to the ride quality. I'd love to minimise the somewhat jarring nature of the Bonnie's passage over the lumps & bumps of my local Hampshire lanes, and I'm anticipating replacing the fork springs with ones with a progressive spring rate (although one piece of advice I've received suggests this may only firm up the front suspension and prevent excessive dive under braking [not an issue with me], rather than improve ride quality). Additionally planning to substitute the original rear suspension units with ones that haven't been made 'down to a price'. However, nearly all the more detailed info I've found on rear suspension originates from over the pond in the USA.
Are there any forum members that have located useful advice on this topic or actually carried out a suspension upgrade themselves please ? One post on this site mentions an improved ride experience after fitting Hagon suspension units, but when I've gone onto the Hagon website, the model dates only go up to 2013. (Being a newbie, I'm not aware if it's possible to pm post authors so I've not contacted the author, so sorry for my ignorance).
My guess is that the effectivenes of replacement rear suspension units will initially be noticeable as the price of the units increases, but, with the limited suspension travel available in the twin-shock design, buying a set of very costly units will only provide a marginal diffence in performance to a mid price range unit (Comments welcome). Build quality maybe similarly affected. Being a pensioner, I wish to minimise my financial outlay, but at the same time wish to achive my desired objective and not spoil the ship for a ha'porth of tar (sorry young readers, the last comment will be nonsense to you !).
If you've read this far in my novel, many thanks. Any pointers re technical aspects/manufacturers products/suppliers will all be scrutinesed closely with grateful thanks.

 

Incredible response from you Gentlemen, and in such a short space of time. Valuable information for me to ponder over already, which I'm very grateful for. I have a follow-up query for 'thebiglad' please ..... How do I ascertain the actual original unit's stroke length please. In my ignorance I would assume that I'd have to remove one of of the existing units, remove the spring retainer to enable free travel of the slider to measure actual stroke length, but is there an easier way ? p.s. I'm vertically challenged, which means the Bonnie is even more suitable for me than most 'bikes on the market. A slight increase in seat height would be viable and may even assist in getting the beast onto it's centre stand which I can only do after eating three Weetabix washed down with a cup of Castrol R !

 

I'm beginning to get the feel for this Forum already ......Hic, Hic, swerve, hic !
Crispey, I see where you are coming from on maximum spend. With the helpful replies to my post, I'll at least have some useful information to help me tread the middle road between cost and effective performance. One very useful drift from the replies is that at least the upgrade is a worth while endeavour and not a waste of time/money/effort.
HalfTon, Useful suggestion, many thanks, but I now don't need to get my hands dirty (just yet). I've just got my Haynes Manual thro' the letter-box, and I'm in luck as the specs list the suspension travel. It's 105mm on the Bonnie and T100. 105mm, is that a useful measure for your 'lubrication' Crispey (I'm assuming your on shorts by now).

 

Thank-you Steve L.

To Thebiglad: Thank you for the additional info TBL, it's upstairs for thinking, downstairs for dancing eh ! It seems I have the opposite 'overall mass' problem to your good self. My previous 'bike was a 650 V-strom, which was an excellent bike, but with me being vertically challenged and not having the strength to fight my way out of a wet paper bag, I found the centre of gravity a bit high for when I was man-handling it backwards down the ramp out of my 'bike-house. On the road of course, there wasn't a problem. Still, it turns out the c-o-g problem was a blessing, as I've now got the Bonnie. I think it's a couple of Kgs heavier than the V, but as the weight is carried low, the reverse out of the 'bike-house is no longer a problem. Thanks again for your very welcome input. Glynn.

 

Well, it's taken me a while, but I have just got round to fitting progressive type suspension front and rear on my Bonnie. I chose Hagon components in the end. Straight forward replacement of front fork springs with progressive rate springs and 2810 units at the rear end.

I did the fork springs first then did a road-test. Perhaps I'm not very perceptive in my old age, but there seemed very little difference in the ride quality with the new springs in, although I could perceive (I think) that road imperfections were dealt with better at very slow speeds. It did feel as if the suspension was ironing out the road surface better than previously.

The road test after fitting the Hagon 2810's on the stern revealed a much more noticeable improvement. Bearing in mind the inherent limitations of the Bonneville suspension setup in the first place, the ride was much more pleasant. Whilst the 'bike still feels every bump in the road, there is now a much reduced jarring shock delivered to the kidney area on traversing road imperfections.

I've only done the 8 mile test ride so far, so I don't know if there will be any further improvement in the function of the rear units once they've had more miles put through them.
(Being of a nervous disposition, I didn't want to push my luck with a longer ride until I'd let my insurance company know of the suspension mod. I'd checked with them before getting the components and there weren't any issues, they just needed informing once the mod had been carried out. It's a point worth bearing in mind. In the unlucky event of having a prang, insurance companies will latch on to any un-notified modification to avoid reducing their profit margin by having to pay out. Any oversight by motorists in this area could work out to be very expensive indeed, especially if a serious injury component is in the claim).

The bottom line is that I'm pleased with the result of the upgrade, but if asked, would suggest it's not worth the hassle/expenditure of doing just the fork springs on their own.