Sidecar on ST 1300 Fork springs too soft.

[aum]

Hello Flexit. Thank you sir for the links. I will spend some time exploring those sites. I have logged in to Sidecar.com in the past. Lots of great knowledge there! If its not too much trouble, could you post a couple pics of your rig? I have added a 3/4" preload spacer on top of the stock spring"s existing spacer and it helped alot, but I am going to order a pair of the 1.2KG Sonic springs to try out.
Thanks
Rick.

Hi Rick,

I am deciding on whether to upgrade the springs on my ST1300 with a motorvation formula ii sidecar, since I will have the front fork rebuilt soon (due to a seal leak). I was curious how the 1.2kg sonic springs with the 7.5wt oil turned out for you.

After inquiry with Sonic Springs via email, they had mentioned the following based on 165lb rider:

"thanks for contacting us!

For sidecar applications it is our experiences that sidecar loads are taken by the rear suspension and do not significantly affect the fronts springrate. At most maybe skew up one size. For your weight I would suggest 1.10 kg/mm springs."

They also provided links to recommended 5wt oil.

Their recommendation kind of took my by surprise, as I see a majority of forum discussions siding with going to 1.2kg to with 7.5wt. What my thoughts are, if I am riding 2 riders plus gear, wouldn't the added stiffness would be better?

Either case, any first hand information with a rig would be appreciated.

Thank you for your time,

Earl

P.S. Your rig is a thing of beauty.

 

[PoppaCross]

GADZOOKS - Heath you complete and utter philistine! How could you violate and defile a saintly Yamaha XS650 with a sidecar?

I am shocked and appalled and so is Aunt Mildred - young man!!

“Saintly 650? When the were still in print they were considered boring but reliable and a bit doggie. I was involved tangentially in the culture having owned two XS 1100’s the first was a Midnight Special with a full Vetter kit. And a real beast. The second was a standard with a WINDJAMMER faring and soft bags. It was also a beast. After putting ten thousand hours on each unit I can tell you this. The twins were reliable it you cleaned the triple tree mounts every six months. Same with the quads. Avoid the triples like a case of the clap.

 

[PoppaCross]

Hi Frank, Thank you Sir, for the photos,and awesome links to Flexit history,and information. This is all very interesting to me,and I plan on spending some time looking at everything you linked to. Your Flexit rig is beautiful,and so very unique! That windshield....I love it, what a cool design! Its a real shame the joint venture with California sidecars didnt work out long term,and they had a falling out, or we would possibly have availability of to a modern "flexit" today.
Thanks again,
Rick Duarte

Hi Rick,

I am deciding on whether to upgrade the springs on my ST1300 with a motorvation formula ii sidecar, since I will have the front fork rebuilt soon (due to a seal leak). I was curious how the 1.2kg sonic springs with the 7.5wt oil turned out for you.

After inquiry with Sonic Springs via email, they had mentioned the following based on 165lb rider:

"thanks for contacting us!

For sidecar applications it is our experiences that sidecar loads are taken by the rear suspension and do not significantly affect the fronts springrate. At most maybe skew up one size. For your weight I would suggest 1.10 kg/mm springs."

They also provided links to recommended 5wt oil.

Their recommendation kind of took my by surprise, as I see a majority of forum discussions siding with going to 1.2kg to with 7.5wt. What my thoughts are, if I am riding 2 riders plus gear, wouldn't the added stiffness would be better?

Either case, any first hand information with a rig would be appreciated.

Thank you for your time,

Earl

P.S. Your rig is a thing of beauty.

Would you post the budget and parts list for your sidecar build. I have a 91 but I want to include the wife in my rides. I’m not strong enough to go two up anymore so a sidecar conversion might be a solution for us. The old girl has the power for a sidecar so that’s not an issue. Me putting the wife safely on the bitch pad is the issue.

 

[Sadlsor]

Just FYI, we haven't seen @bigbikerrick since Feb this year, and @aum since April.
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