Input needed please on upgrading rear shocks on CFMOTO Jetmax

At the moment my Jetmax 250 has standard shocks with a 5.5mm spring wire thickness which mostly seem fine albeit a bit firm on setting 3 , I have never bottomed out on this setting.

With my wife on the back they dont cope when set on max setting (5) . They dont appear to sag much so seem to support the weight but hit a bump and it bottoms out on the stops and on occasion the centre stand hits on corners.
I took care of the center stand issue by putting extenders on giving an extra inch of clearance but it doesn't stop the shock from bottoming out.

I am not about to spend 1/3rd or more of the bikes price on olims or some other brand, I just need something better than it has.

I was looking at these for around $150. They are longer so no need for extenders.
Working stroke is similar as I have now but max loading I would think is considerably more.
Spring thickness: 7.10mm
Working stroke: 56.00mm
Max loading: 300kg / 650 lbs
http://www.ebay.com.au/itm/151582161...%3AMEBIDX%3AIT

These could be better again as they have a thicker spring and longer stroke but they are about 4mm longer than what I have now, which means I may need to mod the centre stand..
Spring thickness: 8.10mm
Working stroke: 70mm
Max loading: 300kg / 650 lbs
http://www.ebay.com.au/itm/YAMAHA-XV...item1e953259ee

They also have the same length/travel version of the above with a 7.1mm spring
http://www.ebay.com.au/itm/SUZUKI-GN...item234fbaf076
Eyes can be changed for toggles on request

Which ones?

Would I be right in thinking that I would probably be able to ride one up on the lowest setting and possibly have a less harsh ride compared to now and probably only need to go up a notch or two with the wife on the back seeing as they appear to have a higher max loading and a thicker spring?

IMO only your experimenting with replacing the rear shocks will provide the answers you are seeking.

That said, if you head over to BurgmanUSA forum you will find some Burgman650 riders have replaced the rear shocks on the 650cc scoot with various air shocks with fairly good results. Here's one BurgmanUSA forum post dealing with the Burgy suspension. Interestingly, I don't find the shocks on any of my Burgman650's to be all that harsh. Okay sure the Burgman650's suspenders aren't remotely like riding dual sport bikes and thus don't offer as plush of a ride as my XT1200Z or 650GS provide on the knarly stuff. However slowing down and taking time to pick lines and navigate the less than ideal road surfaces pay dividends IMO. Now the Jetmax has an even harsher ride than the big 'Burgy' but it's not much different to a Majesty250 or PCX150. Actually I have just taken delivery (Saturday 21st) of a Electric 144v scooter (BMW C600 copy) and it has an even harsher ride since it has 13" wheels when compared with the Jetmax.

What you describe is fairly typical with scooters, and I'm referring to maxi scooters. By design with the smaller wheel diameters and therefore shorter shock stroke the ride over anything less than smooth asphalt or concrete will provide a harsh ride. The Jetmax is similar to many scooters in that it doesn't have full length front forks, unlike the Tmax500 or Burgman650, which do. The Honda NC700D or NC750D Integra has 17" wheels fore and aft which make a significant difference on ride quality too. I went a slightly different route for improving the ride quality on the Jetmax. I added a seat cushion including a combo gel seat posture-pedic (Japanese) cushion and changed the front and rear low profile tyres to Bridgestones... all this helped. I did try a pair of local branded rear gas (with reservoir) shocks, but found little improvement so went back to standard.

Here's a couple of photos of the electric scoot...

Attachment 17519

Attachment 17520

Interesting scoot and thanks for the reply and I'll sign up later to the burgman forum to look at the pics.

The firm ride I can live with
The bottoming out I can't.

I have to do something as I have visions of a broken swingarm like prince666 ?? posted a picture of.

Given what I have said above which of those shocks I linked to do you think would be the best one to go for?
I think the 70mm travel is a given but 7.1 or 8.1mm wire Vs the 5.5 I have now?
And are they what you would describe as air shock?

Well thanks for the link to the Burgman forum experiment.
Much reading there which led me to several other forums and a pile of research.

I have found a pair of Showa Air Shocks in Australia that appear to be in near new condition asking for less money than the Chinese shocks I was looking at so fingers crossed that I get them and it all goes to plan after a bit of creative metal fab and welding.

Well, got those air shocks and very shiney and pretty they are.

The previous owner said they had 65mm of travel, a couple of mm more than the standards.
Reality was they only have 45mm.
Attachment 17617
To modify them I need to weld flatbar to one of the lower eyes to make a clevis and I need to grind 1mm of each side of the top eye face (plenty of metal remains) for it to fit in the top bracket.
Doing this effectively ruins the shocks for resale if they don't work.
I had already made the bracket for the eye side to the same dimensions as the original bracket, just a bit taller where the shock bolts in and that hole will be determined by height after clevis side is bolted in.

Now, do I ruin these shocks with 45mm of travel hoping that their superior dampening abilities will outweigh the 23mm less travel that the original chinese ones had?

Or do I re-sell them and get something like these with heavier wire and 68mm of travel instead?
http://www.japbikespares.com/jawa-25...hock-absorbers
I will have to modify the eye on one, I am hoping I could do something like this.
Attachment 17618
As the centre to centre will be different to the other side, I can use the bracket I have already made and drill the mount hole to match lengths.
Any reason why not?

Hi Seven of Nine

As you are aware I have the CF Jetlux same engine same shocks set up.

With over 20.000 km on the Jetlux one improvement it needs badly is with the back shocks.

This was on my list to do but because of other purchases with new bikes I never got round to doing this mod.

Now because you have asked help in this matter here is my 10 cents but the links are from Taobao in China but I am sure if you see stuff you like I am sure someone on here could help you out.

Most rear shocks come with a "eye" to "eye" fixing point but with our bikes it come with a eye to slot fixing point.

I see you are modifying the shocks you have purchased to suit your needs, but here is a link for some adaptors which you can use when you have a set of shocks with screw in ends.

https://item.taobao.com/item.htm?spm...e-d66d2b1e5cc7

So you can have 1 eye end and 1 slot end.

Here are links to guys on Taobao who sell shocks to fit our bikes with slot and eye ends, all you need to tell them is the eye dia and slot size with the measurement between the centre of the eye and the slot hole if that makes sense.

links......

https://item.taobao.com/item.htm?id=....AcmAt5#detail

http://item.taobao.com/item.htm?id=3....AcmAt5#detail

https://item.taobao.com/item.htm?spm...6-f4fe59207027


Attachment 17623


Attachment 17624


Attachment 17625

Hope this helps

IMO try and buy a new set with "eye" to Slot and not use the set you have, need longer travel the longer the better (The travel of the rear shocks should not be greater than the ground clearance under the bike), and not the set from the link there are eye to eye no good even if you Mod them ?

P.S. The cutting and modifying the end Eye will cause metal Fatigue/stress and will most likely will fail at some point not a good thing to happen with the rear shocks under load.

Quote:

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Originally Posted by prince666

Hi Seven of Nine

As you are aware I have the CF Jetlux same engine same shocks set up.

With over 20.000 km on the Jetlux one improvement it needs badly is with the back shocks.

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Hi and yes, I knew that.

Quote:

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I see you are modifying the shocks you have purchased to suit your needs, but here is a link for some adaptors which you can use when you have a set of shocks with screw in ends.

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The links in my first post are to a version of the same purchased through a local reseller.
He claims his are made by an ISO9001 Compliant Manufacturer so I would like to think they are better than some of the other cheapies - maybe not.
He can supply one with a screw in clevis like you show but you end up with one shock longer than the other.
even if he screws the clevis all the way in and the eye out as far as he is game there was still about 7mm of difference.

What I did find out about some of the "no name" cheap piggyback shocks is that they do have issues as you'd probably expect given the price.
Mounting brackets were mentioned by some as failing.
RFY seemed one of the better brands and mentioned most but still have issues - but they are rebuildable
http://chrislivengood.net/wp/rfy-sho...build-service/

Quote:

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P.S. The cutting and modifying the end Eye will cause metal Fatigue/stress

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Are you sure about this for a one off bend?
If the bending cycle was repeated I agree it'll fail but not so sure if done once, after all, the clevis brackets on steel shocks when new are bent to that shape and welded.

Quote:

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Are you sure about this for a one off bend?
If the bending cycle was repeated I agree it'll fail but not so sure if done once, after all, the clevis brackets on steel shocks when new are bent to that shape and welded.

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No i am not sure ??? just IMO

Maybe if you can apply some heat when you decide to carry out this action "could" help.

I am sure you will sort it out and good luck.

Quote:

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Originally Posted by prince666

Maybe if you can apply some heat when you decide to carry out this action "could" help.
.

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Nah, heat would be a bad idea due to being oil filled.
If I could do that I'd just cut the eye of and weld a clevis on.

To confirm my thoughts I did speak to a motorcycle shock rebuilder here and he said cut and bend would be OK if done right and it would be far from the weakest part of the shock.
He did say under no circumstances to weld or apply heat to the shock itself due to oil or gas charge.

Annoyingly enough I went out for a 350klm round trip today and before I left I wound the shocks off a click and it all felt very comfortable so if it was just me I wouldn't be bothering.