Any advice on Bonneville suspension upgrade please ?

Discussion in 'Technical Help' started by Glynn Hallett, Nov 8, 2015.

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  1. Glynn Hallett

    Glynn Hallett New Member

    Oct 20, 2015
    6
    3
    Fareham, Hampshire, UK
    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.
     
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  2. Recycled Rocker

    Recycled Rocker Senior Member

    Apr 19, 2014
    353
    113
    North Yorkshire Cave
    Yo Glyn, welcome aboard, Progressive springs good on front but some suppliers state 20W fork oil whereas TEC suggest that's wrong should be 10W. I put TEC rear gas shocks on my 2009 Bonnie SE. These were about £99. I appreciate yer point about dearer ones might be better ie not built down to price. However others on here will give sound advice about what they did. After that personal choice as always, good luck :)
     
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  3. MattGaydon

    MattGaydon Noble Member

    Jun 11, 2015
    818
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    Godalming
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  4. thebiglad

    thebiglad Old fart, still riding !

    Sep 25, 2013
    5,126
    1,000
    Central France
    Hi Glynn, I used two different pairs of TEC shocks on my 2010 T100 and found both a significant improvement of the std. items.

    You have two basic areas of choice :

    1. Replace the rear shocks with the same length/stroke as the std. ones OR as I did did replace the the STD 340mm overall length jobbies with 360mm Scrambler/Thruxton length ones. It raises the seat height slightly, gives greater ground clearence and a slight increase in steering responsiveness.

    2. The make/supplier of the replacement shocks - the front runners seems to be TEC with their range of rear shocks at £85 to £130 the pair or Hagon at approx £200.

    In both cases, check the stroke of the shock, not just the overall "hole to hole" length. Also if like me you are Man-sized rather than boy-sized, on request George at TEC will supply a second pair of springs of a slightly heavier weight to support larger loads. :oops::rolleyes::rolleyes:
     
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  5. Glynn Hallett

    Glynn Hallett New Member

    Oct 20, 2015
    6
    3
    Fareham, Hampshire, UK
    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 !
     
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  6. crispey

    crispey crispey creme de la creme

    Nov 6, 2014
    7,318
    1,000
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    Hi Glynn welcome in, yeah they all like the sound of their own "voices" on here. I for one will go along with Halfton on the Hagon 2810's and will fit some soon, but not to upset some people on here, sensitive the lot of 'em, TeC's are also reportedly value for money and do their job, any thing that bounces back with the biglad sat on them must be doing their job well. I would not bother spending more than £250 as the style of bike and riding would not really do the more expe3nsive one justice
     
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  7. thebiglad

    thebiglad Old fart, still riding !

    Sep 25, 2013
    5,126
    1,000
    Central France
    You cheeky bastid !!!!!
     
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  8. crispey

    crispey crispey creme de la creme

    Nov 6, 2014
    7,318
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    [​IMG]
     
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  9. thebiglad

    thebiglad Old fart, still riding !

    Sep 25, 2013
    5,126
    1,000
    Central France
    There's just no holding you is there? Have you been drinking?
     
  10. crispey

    crispey crispey creme de la creme

    Nov 6, 2014
    7,318
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    Uk
    not yet!!
     
  11. stevethegoolie

    stevethegoolie Elite Member

    Oct 16, 2014
    2,482
    800
    East Riding of Yorkshire
    But he will!!! :D:D:D
     
  12. crispey

    crispey crispey creme de la creme

    Nov 6, 2014
    7,318
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    HIC!! And I did!!
     
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  13. Glynn Hallett

    Glynn Hallett New Member

    Oct 20, 2015
    6
    3
    Fareham, Hampshire, UK
    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).
     
  14. crispey

    crispey crispey creme de la creme

    Nov 6, 2014
    7,318
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    no got the mother of a hang over, that's what comes from following half a bottle of port with cheap whiskey [​IMG]
     
  15. thebiglad

    thebiglad Old fart, still riding !

    Sep 25, 2013
    5,126
    1,000
    Central France
    Hi Glynn, the answer to your question has already been partly given by Half Ton and partly by Haynes, but what I was getting at is the stroke of the shock absorber that is being used!

    So as Half Ton said, attach a zip tie to the piston rod on each of the shocks and position it so that it's initial position is just under the main cylinder of the shock (the bit the rod goes into) whilst the bike is still on it's centre stand. Then go for a ride on a route that takes in all the lumps, bumps and rough terrain of an average British road.

    Now put the bike on the centre stand again and look at the position of the zip ties. If you've done it right the zip ties will now be a fair way down the piston rod and this is the amount of stroke actually used. I found that due to my somewhat ample girth the zip ties had gone right down to the bump stops when I was carrying my trip luggage (or a passenger), showing that the std springs on the TEC shocks were not up to the task required of them. I changed them for the heavier-duty set provided free by George and all was good.

    This highlights an interesting point. The springs need to be strong enough to hold up the weight of the bike, plus any loads you put on it. Some will argue that's what spring pre-load is there for, but I've never had that much success with it on any of my bikes except the BM's.

    Think carefully about what loads you'll regularly ride with : passenger yes/no? Luggage yes/no and tell the shocks seller the results.

    The best of luck to you, I hope that helps.

    Dave
     
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  16. steve lovatt

    steve lovatt Something else
    Subscriber

    May 12, 2014
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    Hi Glynn and welcome to the forum - which you now have some experience of!
     
  17. Glynn Hallett

    Glynn Hallett New Member

    Oct 20, 2015
    6
    3
    Fareham, Hampshire, UK
    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. :)
     
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  18. Glynn Hallett

    Glynn Hallett New Member

    Oct 20, 2015
    6
    3
    Fareham, Hampshire, UK
    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.
     
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  19. Bikerman

    Bikerman Crème de la Crème
    Subscriber

    Oct 29, 2014
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    An honest report to your mods. Any chance of some pictures of your steed ?
     
  20. t552

    t552 Senior Member

    Nov 17, 2014
    411
    113
    Bristol UK
    Must say my preferred rear is Ikon, the old Koni dial a rides.
    I was always told use linear springs on progressive from Maxton. Just my curve ball lol.
     
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