Viper 640 Class Association Forums

Viper 640 Public Forums => Viper Discussions => Topic started by: TicTacUFO on March 24, 2026, 07:58:09 PM

Title: Spinnaker trims, jib sheets & hiking stick lengths
Post by: TicTacUFO on March 24, 2026, 07:58:09 PM
We recently purchased a used viper that needs new 7 mm spinnaker & 8 mm jib trims as well as a longer hiking stick.

I was wondering if I could get some opinions on what type/mfg lines people are using and what length they should be.

 In addition, I've sailed Vipers with too long of a hiking stick, and now one that's too short. Just like Goldilocks, I'm trying to find one that's just right. I'd love to know what hiking stick length works best.


Title: Re: Spinnaker trims, jib sheets & hiking stick lengths
Post by: Eddie Wolfe on March 26, 2026, 11:38:42 AM
The first step is to read the class rules, and adjust your turning block on the mid-boom over the mainsheet cam cleat, and move it forward to the maximum allowed by the rules. Used boats almost certainly are not at this setting, so you'll gain an inch or two of pass-through space.   Once that's done I prefer a telescoping tiller extension, and use this one: https://www.amazon.com/dp/B002NSO0D0?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_1. It will go further than the rule permits, but shorter as well so leaves some adjustment for various helmsman sizes.

As far as lines I've had good luck purchasing them from a class vendor, Several are posted in association with the class: note Tapered sheets on the spin are now permitted, so you may want to consider that.  If you want to go purchase your own there are threads on the forum about this including here: https://forum.viper640.org/sailing-handling-tips-and-techniques/please-help-line-lengths-what-are-you-using/
Title: Re: Spinnaker trims, jib sheets & hiking stick lengths
Post by: TicTacUFO on March 27, 2026, 08:32:39 PM
Thanks for the advice on the boom block. I'll definitely look into that.

However, the only post I could find about sheet lengths is the same one you referenced. Unfortunately, that post is from 2009 and only ONE person gave the lengths they use, but they use a continuous jib sheet. Moreover, he recommended 3/16 (4.8 mm) spinnaker trims of 84 feet. Since he's recommending 3/16, I am skeptical about his 84 foot length recommendation as well. Vela Sailing told me 68 feet, but they don't say what line they are using. I've also heard 72 feet.

If some of the class experts could share what length & type line & setup they are using for their spinnaker and jib trims, I'm sure it would be helpful to a lot of people, not just me; although, I'm about to purchase new lines and would love to hear some recommendations, especially on spinnaker length.

I was thinking of Dinghy Sheet XL 8 mm from Robline for the jib trims
And
Marlow Excel Fusion 7 mm spinnaker trims.  As far as how long they need to be...

Title: Re: Spinnaker trims, jib sheets & hiking stick lengths
Post by: Eddie Wolfe on March 28, 2026, 08:45:35 AM
The advice in the referenced thread is indeed from ONE person, but that ONE person was the technical comittee chair at the time.  Provided the Viper is a ONE design and it's dimensions don't change, the advise is still valid.  Their program is still active in the class, you could reach out to them for additional context.

You've also misread the post. Dave mentioned 72' 5/16's NER Flight Line for the Spin Sheet.  The 84 foot 3/16' dimension is for the spinnaker halyard.  If you don't want to use a continuous Jib sheet for some reason then cut the referenced length into two pieces. There aren't many (Any?) boats in the class doing that.  Best of luck.