SL: Series 'D' Enclosures Black Prince Seat Height

tom wilson

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Hi I shall soon become a new owner of a Black Prince .... cannot wait. I only have a 29" inside leg and I would love to lower the seat height, I would have thought some Vincent owner out there has reduced the seat height .... I cannot be the only short legged owner! What would/will be the best way to lower it without affecting the handling ... shorter spring, softer spring, multi tension spring or can the spring mounting points be lowered etc. Does someone out there has the answer? No I do not want to wear platform boots or carry ladders etc.
 

tom wilson

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By coincidence, I have just ordered the short version of the AVO damper and expect it to arrive this coming Wednesday. I've been living with my open D's seat height for years but finally decided it needs to be fixed. Two weeks ago, I dropped the bike in a parking lot and wound up with an AC shoulder separation. It's healing well, not very serious but I don't want to go through that again. The reason for the fall was that as I was making a tight turn out of a parking space and some *******bloke jumped out in front of me to park his car. My right foot didn't reach the ground soon enough.

My inseam is more like 28" so I need to make this correction. I'll be mounting the AVO this coming week and will post my observations.
Gary

P.S. The bike didn't sustain any damage, thanks to it's homemade crash bar.
Hi Gary thanks for getting in touch, I have just had an email from AVO (Neil) said he was not sure if his system lowered the seat height or not and suggested I look on this site (I always try to stay one step in front ha, ha). Would you be kind enough to let me know your thoughts as soon as you have fitted the AVO? many thanks Tom
 

tom wilson

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If you fit a JE steering stem with the softer springs that will soften up the front end. If you still have the original long 'D' springs on the front they will be too stiff with the AVO. One thing that we older chaps use to do with a 'D' was to either sit on the bike or stand at the side and push up and down on the saddle where one sits. The front and rear of the bike just used to go up and down by the same amount. It used to be a remarkable demonstration of the comfort of the 'D's and also a test as to whether one had adjusted the clearances on the girdraulics correctly.
TT What is a JE steering stem and where do I get one from> also who stocks the softer springs? having had 'only' series C models I am not up to date with the 'D' world, cheers
 

kerry

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Tom,
see my earlier message below,
These do lower, I have done 3 so far. in my experience about 1,1/2" which makes a big difference.

Hello, I have 29" Legs and can sit on my Prince or open D with both feet flat on the ground !
I have fitted Avo on both, the following is the part numbers from AVO

1 off PC1590 D coil over damper
1 off A9300 1.9" Coil Spring

Total cost £264. Gives a really nice ride, if you are though taking pillion passengers or are heavy you may consider a different spring.

Personally I think a D gives a better ride than a C series but I am not sure of the best damper for the front on a D, I have fitted AVO here but feel they do not perform brilliantly like the rear, just my own view.

Kerry.
 

timetraveller

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Is it possible to fit softer springs into existing spring boxes ?

The problem is that the springs are shorter to match the geometry of the new steering heads. The springs are 16.5" long for the 30, 33 and 36 lbs/inch springs and 15.5" long for the 45 lbs/inch ones. Ernie wanted to try this several years ago but I have never heard from him as to whether he ever fitted them. My opinion was that it would not work but lacking feedback I truly do not know

.TT What is a JE steering stem and where do I get one from> also who stocks the softer springs? having had 'only' series C models I am not up to date with the 'D' world, cheers

Tom if you send me an email to enw07@btinternet.com I can send you the fitting instructions for the JE stems so you will learn a lot about them. They are nothing to do with 'D' although they will fit on them. You can only get them from me and I am just in the process of making up a batch of 20, which has increased to 21 during the operation. I also supply the springs. Please read the instructions as there are a lot of options and you can choose as much of a complete package as you want. In very round figures the minimum would be £400 and the maximum about £1,000, (That includes a rear AVO coil over which is about £260 on its own.
 
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Gary Gittleson

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I should mention that I have had Timetraveller's JE steering stem installed for a while now and am very pleased with the setup. I have his steering damper as well and the ball-bearing lower bush replacement. All great stuff. Works just fine on my D. By the way, my front damper is a Thornton which is no longer available but works just fine.

Yes, I will report here as soon as I have mounted and tested the new AVO. It cost me £210 but I suppose that's without the VAT but then £40 added for shipping to the US.

Gary
 
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BigEd

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Copy of article I did for MPH about the AVO units I developed and two owners tested.
Speaking as an early tester and satisfied user, you will find that this is a really simple "plug and play" suspension option to improve comfort on a Vincent. Units are usually available off the shelf and in this day and age, reasonably priced for what is such a low-volume product. We are lucky to have companies like AVO who are willing to produce these custom units and people like Rob who was tenacious in persuading AVO to develop and produce them in the first place.
 

kerry

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Totally agree with Eddy, Thank you Rob and Avo for making these available so shorter people can ride D's.
I have fitted 3 of these in the past 18 months, Avo send them next day, as I said, in my experience they lower up to 1,1/2" and give a better ride, the road tests of old criticise the height on D's, someone should do a road test today.
I have lowered the centre stand on all 3, not essential but much better after.
Kerry.
 
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