Author Topic: Forseti CDI units?  (Read 215 times)

SteveC#222

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Forseti CDI units?
« on: September 18, 2020, 06:55:36 PM »
Has anyone got any experience of Forseti CDI Units?....good/bad.

I'm thinking of fitting an XL600R CDI to my XBR but a 40 year old secondhand Honda part is quite expensive wereas a new Forseti copy is under £20!...if they work OK.

Thanks.
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themoudie

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Re: Forseti CDI units?
« Reply #1 on: September 19, 2020, 12:00:57 AM »
Not a clue Steve.  :-\ Sorry, not to be able to help.

Good health, Bill

mthee

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Re: Forseti CDI units?
« Reply #2 on: September 19, 2020, 11:23:26 PM »
You probably already know this, but just in case, JOOLZ has a word of caution here;

http://www.thumperclub.com/index.php?topic=7514.msg51504;topicseen#msg51504

SteveC#222

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Re: Forseti CDI units?
« Reply #3 on: September 20, 2020, 07:35:59 AM »
Yes I have seen that thread Matt. I have fitted an XL600 CDI in the past - it isn't 'instant racer' by any means but does give a noticeable kick when you crack the throttle open. Big annoyance is you can't use the leccy boot - it blows the fuse!. Thought I might have a play with one again but secondhand Honda one is at least £60+ and this is £18 plus post from OZ. At that price I might try one anyway just to see.
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mthee

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Re: Forseti CDI units?
« Reply #4 on: September 20, 2020, 10:02:56 AM »
Just plug n play then? I'll be very interested to follow this thread, especially given the price!

tevie54

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Re: Forseti CDI units?
« Reply #5 on: September 23, 2020, 01:58:29 PM »
Forseti are a Chinese company who also do pistons. I have had good and bad experience with Chinese made products, they quite often work very well at first but because they tend to use cheap components they don't last long so personally I would buy two just to be on the safe side.

SteveC#222

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Re: Forseti CDI units?
« Reply #6 on: September 24, 2020, 03:38:15 PM »
I've ordered one out of curiosity - works out at £30 with postage so not all the world if it is no good.  Will report in due course when/if it arrives! (though seller has 100% feedback so it should at least arrive).
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SteveC#222

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Re: Forseti CDI units - UPDATE!
« Reply #7 on: October 26, 2020, 06:07:14 PM »
OK, so I ordered a Forseti XL600R CDI unit from Australia - £18.20 + £10 postage so not all the World if it didn't arrive/work.

Well it did arrive after just under a month. Looks pretty good - not obviously poor quality, in fact pretty much like the Honda unit.  Plugs nice and tightly straight into the loom. Started first kick! ( admittedly I had already warmed the engine using the XBR unit but has started first/second kick from cold every time since then.) First thing I noticed was the tickover was higher with the new unit, but revs out fine and noticably quicker revving from tickover.

So far work/ weather has only allowed a couple of 20 mile rides but it works fine and gives a definate improvement in pickup when cracking the throttle ( getting a 14 tooth front sprocket to make the best of it!).

So, overall, seems OK! Long term reliability is obviously a question but it looks well made so time will tell - though I have the XBR CDI is wrapped in bubblewrap under the seat just in case!

If you fancy trying it, it's under £30 - at least half the price of a 40 year old secondhand original Honda part from a broken bike.

JUST REMEMBER! If you do try one you have to disable the electric starter as if you try and use it ,it will blow the main fuse - not sure why, probably because it was designed for a dirt bike with no leccy boot. I have heard there is a way to use the unit AND have a leccy boot on a GB500 with a wiring cahnge but I'm not sure how. Maybe someone out there who understands the black art of motorcycle electrics may be able to provide an answer?
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mthee

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Re: Forseti CDI units?
« Reply #8 on: October 27, 2020, 12:18:47 PM »
Nice find, Steve! Thanks for the report, I might give one a go. What effect does the new front sprocket have on top end, if any?
As far as the question why a CDI from a kickstart-only bike blows the main fuse in one with an electric start, I believe iansoady is our own dark arts master from whom to beseech an answer!🤓👏

SteveC#222

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Re: Forseti CDI units?
« Reply #9 on: October 27, 2020, 04:03:37 PM »
A 14T sprocket should give a bit more acceleration at the cost of a little top end speed. That said I don't ride flat out so a bit more acceleration will probably be more useful - also I find that 60mph in top (4000rpm ish) seems to be the spot where I get a bit of vibration and numb fingers so the slightly higher revs of the gearing change may take crusing speed out of the vibration patch.
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mthee

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Re: Forseti CDI units?
« Reply #10 on: October 27, 2020, 04:21:15 PM »
Double bubble! I'd be grateful for some figures on those anticipated changes whenever you get them?

Oldtimer

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Re: Forseti CDI units?
« Reply #11 on: October 28, 2020, 03:38:14 PM »
A 14T sprocket should give a bit more acceleration at the cost of a little top end speed. That said I don't ride flat out so a bit more acceleration will probably be more useful - also I find that 60mph in top (4000rpm ish) seems to be the spot where I get a bit of vibration and numb fingers so the slightly higher revs of the gearing change may take crusing speed out of the vibration patch.
I changed my XBR sprocket from a 14T to a 16T as it was revving high at 70 but in doing so dropped the top end speed down. It does cruise nice at 70 now and is able to top 95 in top gear. At that speed it is not quite in the power band and to wind he up in 4th does not make a big difference and looses speed on slight up hill gradients.
Mike
Honda XBR500
Norton/BSA Gold Star DBD34 special

mthee

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Re: Forseti CDI units?
« Reply #12 on: November 04, 2020, 01:43:31 PM »
A 14T sprocket should give a bit more acceleration at the cost of a little top end speed.

Copying along to get that extra pickup, is it a standard chain to go with the 14T drive sprocket? Any developments with the new CDI? Thanks, Steve.

I've been searching around for a cylinder and piston off an XL600R ever since JOOLZ said it was best bang for your buck. Am I chasing rainbows here? Maybe the only way to go is have someone work on the existing lump?