[icenian]

Are you able to estimate the working lengths of the spring by measuring the parts? (max length and min length)

If I have understood the problem it is that the choke does not get stuck fully open but more in a part open condition. If this is the case we should try to select a spring that gives more force in this part of the movement (ie same rate but greater free lengh to give more preload)

I like your thinking! The tricky bit if figuring out the length of the srping when everything is assembled.

For the sake of argument, lets say the spring (which has a free length of 21mm) is compressed to 18mm when it is on the choke cable and the cable is connected to the plunger. We could probably measure that. But then when the cable is connected to the carb, it could then be compressed to say 15mm. That would mean the working length is from 6mm to 15mm. But it would be hard to measure how much the spring is compressed when it's all fully assembled :?

:idea:

We can estimate from the cable at the lever? We know the spring compressed to 6mm when the lever is pulled right back. We also know that there is slack in the cable when the lever is pushed forward - at this point the spring must be extended as far as it can go.

If we could measure the cable movement, from the point where it's pulled as far back as it will go to the point where it starts to go slack, we know the the range the spring's working over. This would probably be easier with the lever disconnected.

e.g. if the cable movement is 10mm then the spring is going from 6mm to 16mm.

Now all we need is a AT that has the choke working correctly and we can measure it! If we rule out bikes (like mine) bodged with biro springs, bikes with the choke disabled, bikes that never have the choke used so that it's seized off, and bikes that have chokes that are slightly stuck...

.. is there any AT out there suitable for this :lol:

 

[simon0bikes]

OOhh yes, I'd be in on this. A stitch in time saves nine as they say..and they would be good in the spares box I am going to start. :lol:

 

[Radio-active]

OK...I guess im going to have to look at this as well.....175 miles to a tankfull...with new choke cables(and rusty springs!!) ...so whats the state of play with the research?

 

[icenian]

whats the state of play with the research?

I've been down with the 'flu for nearly 2 weeks, which hasn't helped. Also springmasters haven't bothered to answer my email.

As Grader pointed out - see the fiendishly clever graph above - the free length of the spring and the working length (when everything is assembled) is important to understanding the actual force that each spring would provide.

There some discussion about this above, but pragmatically I see that the C-6603980 (green line on the graph), C-5503840 (pink) and D11480 (dark blue) should give a suitable range of forces whatever the actual working lengths are likely to be.

If there's no advance on this position, I'll try and get prices out of springmasters for supplying those 3 springs.

 

[icenian]

Hope nobody minds that I've been keeping you waiting! Springmasters didn't answer their email and then I forgot for a while

An order of 30 of each spring would cost 72.10 total (incl. delivery and VAT). That's 4.81 per person. Add a bit for paypal fess, postage, packaging...

£6.50 total for 3 pairs of springs

£5.50 if you send me a stamped (44p 1st class, 37p 2nd class) addressed envelope and a cheque.

That price would allow for a small drop in the order size. If everyone you said 'yes' in the poll orders some, there'll be an excess of up to about 50p per person. Whatever excess there is, I'll pass it on to Dave to help towards the costs of running the site.

Please PM me to confirm that you would like a set of springs. Include the email address that I should use to invoice you via PayPal (or tell me if you're sending a cheque and SAE). Please regard your PM as a commitment to buy at the price above.

 

[Roadcat]

Are the choke springs on the 650 the same as on the 750?

 

[icenian]

Are the choke springs on the 650 the same as on the 750?

I don't know, hopefully someone will be along in a minute with an answer. A few posts back, in this thread, I give approximate dimensions for the OE spring in an RD07. You could compare, if you don't mind stripping it down!

 

[Dilbert]

Are the choke springs on the 650 the same as on the 750?

They look the same but a quick check here http://www.cmsnl.com/searchparts.php lists the 650 part for the whole spring/ nipple/ elbow/ plasticy bit (16046-MR1-004) as only suitable for the XRV and NTV 650's, if you've got the part number for the 750 plug it in and see how it matches up.

Knowing Honda I wouldn't mind betting it's the same spring, like Icenian says, you're probably best measuring one up to be sure, or for £6.50 just give it a try?

 

[icenian]

£6.50 total for 3 pairs of springs

£5.50 if you send me a stamped (44p 1st class, 37p 2nd class) addressed envelope and a cheque.

This is embarassing

I need to increase the price to £7.40

The price has risen since I got that quote last month, it's now working out at 6.29 each (sorry about that - I understood the price was constant up to 100 units, but apparently not). Postage is 37p, Paypal add about 40p each That exceeds the margin I allowed for in the 6.50 price, I need to increase by 90p.

 

[simmo2]

No way should you be embarrassed. The amount of research etc you've done on this problem we all have or will have is worth the small increase.

Count me in for a set. Have PM'd you.

Simmo

 

[markh]

I need to increase the price to £7.40

Whatever, it's still cheap. Reading the other posts, maybe someone wants to negotiate a bulk purchase of fuel pumps... :?

 

[DaveS]

Reading the other posts, maybe someone wants to negotiate a bulk purchase of fuel pumps... :?

That's what we have already.
The price we get charged is the same as a bulk buy. They agreed to keep the price going after out initial bulk buy.
I haven't gone out to the market place at all since we negotiated this price so I assume that we're still getting a good deal.
Nobody could match it previously but that may have changed.

 

[icenian]

Count me in for a set. Have PM'd you.

Really sorry, but the order had been placed already when you posted. I guess you didn't spot the sticky LAST CHANCE: order NOW for carb springs thread.

When we've got the springs, and had a chance to figure out which ones work best (and if any of them actually work at all!), we'll post the part number. Springmasters have a minimum order of 15 pounds (plus 7.50 P&P, plus VAT) but that's not so bad if there's 4 or 5 people wanting springs.

 

[YEN_POWELL]

£6.50 total for 3 pairs of springs

£5.50 if you send me a stamped (44p 1st class, 37p 2nd class) addressed envelope and a cheque.

This is embarassing

I need to increase the price to £7.40

The price has risen since I got that quote last month, it's now working out at 6.29 each (sorry about that - I understood the price was constant up to 100 units, but apparently not). Postage is 37p, Paypal add about 40p each That exceeds the margin I allowed for in the 6.50 price, I need to increase by 90p.

No worries at all, I'll post the extra asap.

 

[Dessert Storm]

Oops. This was a message to say I'd take a set for my TA (on the basis that it's worth a chance at seven-quid odd that they are the same size). Then noticed the 'closing date' post. I'll get my coat.

 

[Radio-active]

:laughing3:


Your not the only one :roll:....Im going to see how the lads get on & if its a good fix, then look at ordering another batch, seems like we need a minimum order of about 10 pairs of springs at around £3 a pair plus postage.

Who else is interested?

Do you think we could twist DaveS's arm to stock them in the shop as it seems everyone will need them sooner or later! :teeth:

 

[johntaylor]

Yeah I am interested for sure. I have followed this thread all the way back and recognise all of the symptoms from my own bike. A question though - if is not the springs that are the problem but is the cable will I get new springs when I order my outrageously expensive cable from honda or would they come seperatly??

I'm in on the springs what ever!!

 

[Radio-active]

If you buy the £40 Honda cable or £11 patern cable thats what you will get!...from reading threads on here, the service kit for the carbs includes the plastic nut, the spring and the metal 90° bend, not sure about the plunger! and costs about £40 per carb....the delicate plastic nut and the spring are the two bits your most likely to need.

I dont know if this is everyones experience but the front cylinder carb is the most likely culprit, the cable has a more torturous route and across the top of the (hot) rocker cover.

Im just waiting to see if these new springs are a fix then well sort out an order :thumb:

 

[icenian]

Confirming what Radio-active says: the cable is just the cable. You do at least get all 3 parts and the splitter, Honda don't charge another 40 quid for that :roll:

The "starter valve set" contains the 90 elbow bit, the rubber sleeve that goes over the top, the plastic nut, the spring and the plunger. You need to buy one set for each carb., for about 40 quid.

So to change the whole lot sets you back around 130 quid :evil: :evil: :evil:

Wemoto are a wee bit cheaper. A pattern cable is about a quarter the price of Honda, and maybe half as good (I'm guessing water and dirt penetrated more easily, as the ends aren't sealed at all and the splitter box is a bit mickey mouse). Which maybe means a pattern cable is better if you don't mind changing it more often and want to save money; but if you find the job a bit of a chore go for the Honda one?

 

[icenian]

Here's a picture of the 3 replacement springs, and the OE spring.

They are labelled by springmasters part number:
C-6603980 (similar to OE), C-5503840 (stiffer) and D11480 (stiffest). Thanks to grader for figuring out which ones should be best.

Those who have paid (thanks, and sorry to keep you waiting!) should get their springs by the weekend.