Should I change front fork springs ?
- Thread starter aSTerix
- Start date
Springs only support weight, and shocks only resist motion. If the spring lengths still meet specs, there's no advantage to replacing them unless you and/or your loads are very heavy.
Now thats getting very personal ! yes I would say I am heavy
"Should" is not something I can evaluate. Are you looking to change the ride / handling charateristics? If so, that's one way to do it.
kiltman
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- Joined
- Apr 27, 2013
- Messages
- 3,275
- Age
- 68
- Location
- Stratford, Ontario Canada
- Bike
- 2002,ST1100ABS
- STOC #
- 8826
You might consider a heavier viscosity of oil, that will change the rebound a bit
The standard 1100 was always considered undersprung at the front with a lot of sag as standard. Many 'solutions' were put forward, such as extra preload with water pipe spacers and/or heavier fork oil and also different springs. I don't know about modifying the ABS version - it's up to you to gauge what you think best. It's a shame you don't get the standard fork oil drain plugs.
Many ST1100 riders (including myself) have replaced their OEM fork springs and rear shock with Progressive brand items. I found that the spring replacement greatly improved the front forks' tendency to dive hard under braking, and coupled with the rear shock just made for a more enjoyable ride, especially with a pillion rider. My experience, YMMV.
RobbieAG
Robert
To determine if you should change springs, you need to check your sag. That will depend on your weight. There are many YouTube videos and articles on the web how to do so. Changing springs to be appropriate for your weight is probably the most cost effective way of upgrading your suspension and motorcycle in general. They generally run around $100. I changed the fork springs on my 1300 and it made a huge difference. I went to straight rate springs rather than progressive (stock). I feel that the stock 1300 is under sprung. The sag with me (175 lbs) on the bike was around 50 mm while the recommended number is around 30. You can also change the sag by adjusting the preload. That would be even cheaper. Since there's no adjustment on the forks of these bikes, you'd have to cut some new spacers. That may or may not work depending on how far off the recommended number you are.
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okckeith
Site Supporter
Yes you should. But find out what is the right spring for your weight. Then go enjoy your bike.
I did the same thing when my fork seal went out on my 1300.
+1 on @RobbieAG. Search for other threads here on measuring and adjusting your sag, or even RaceTech Gold Valves (sag has been discussed in threads on both subjects). Once you know your sag, you can determine if you need new springs. Measuring the length and comparing it to specs simply tells you if your spring is worn out or still usable, but it does not tell you if it is adequate for your weight*. Should your sag be slightly high (over 30mm), you can bring that back to spec range by using a longer spacer at the top of the shock (against the spring). PVC plastic drain pipe (1 1/4" tailpiece for a sink) works great and is very cheap. I have no idea what they use in your neck of the woods for plumbing. Maybe only metric sizes?
*By your weight, I mean you in full gear (helmet, boots, clothes, etc. plus the normal gear you always carry in the saddle bags/tank bag, as well as whatever ironmongery you keep in your pockets on a daily basis(spare nuts & bolts, pipe wrenches, dumb bells and such).
*By your weight, I mean you in full gear (helmet, boots, clothes, etc. plus the normal gear you always carry in the saddle bags/tank bag, as well as whatever ironmongery you keep in your pockets on a daily basis(spare nuts & bolts, pipe wrenches, dumb bells and such).
I weigh about 190lbs and was not happy with the handling of my ST1100A2 early on. (02 abs). 43mm fork, with soft plush progressive springs. Most people liked that set up but not me. I replaced the oil with a blend of honda spec fork oil (SS-7) and AMSOIL shock therapy suspension fluid #10 and replaced the springs with linear springs from Race Tech, not the valves just the springs. This way I didn't have to remove the forks. Stiffened up the front just enough i was happy with it. Soon as I did that I hated the stock rear shock...I've been through four windshields, three brands of seats and three brands of rear shocks to get her where I wanted. Beware the Obsessive Modification Disorder. OMD is highly contagious
If you weight 130 pounds, your probably ok. However, we all don't weight the same as Honda's test engineers.
I have a ST1300, and when one seal began leaking at 120k, it was time. I replace the seals, dust seals, don't forget the bushings and fork springs. (recommend only OEM seals, dust seal set) 10 weight Honda fork oil. I went from the stock 0.86 kg/mm springs to 1.00 kg/mm for my weight. It took 3-to-4 attempts to get my preload spacers cut at a length to support my sag. Started out at the stock oil level and had to add 10cc a couple times during preload spacer changes.
I knew the rear shock was dead and riding on the OEM soft spring, so I changed to a (REBUILDABLE) Penske rear shock and it improved the ride greatly. If your going to invest in a rear shock, don't go with the $500 non-rebuildable shocks).
Good luck and have fun riding.
