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Front Sprocket details

Posted: 21 Oct 2019 17:36
by davel182
Is anyone able to confirm (or refute) that part number 19.01.39 is the 520 version of the standard 19.01.31 front sprocket (14t) and, if so, does it have 12 splines approximately 20mm o.d. / 18mm i.d., and does it use the stop ring (22.01.54)? I don't have a 500 but the 250 single and since I cannot find a front sprocket to fit (428), I am hoping the splines might be the same on the 500, and convert to 520. I did email Richard at Mdina but, as sometimes happens with enquiries, no response. If it doesn't have the stop ring, what stops it going on too far and out of alignment?

Thanks for any help.

Dave

Re: Front Sprocket details

Posted: 22 Oct 2019 15:13
by mbmm350s
Hi Dave

19.01.39 is the 501 camel sprocket.

I cannot see the stop ring part you refer to in the Camel parts book,
hopefully a Camel owner will be able to help.

The camel 501 owners book says transmission is 14/46

Sorry I cant help more.

Mark

Re: Front Sprocket details

Posted: 22 Oct 2019 16:08
by davel182
Thanks Mark

Mdina actually have a picture of 19.01.39 so I can see there are 14 teeth and 12 splines and the description includes 520; with them having 47 units, I just assumed it might be the 520 version of the 'normal' 500. But it might still be OK if the splines are the right size (for me). For the 250 I would (probably) use a 44t rear.

Re: Front Sprocket details

Posted: 22 Oct 2019 20:10
by mbmm350s
HI Dave
I would order it anyway I am sure you will be able to workout how to get the offset correct even if you need to modify the sprocket.
Mark

Re: Front Sprocket details

Posted: 22 Oct 2019 21:35
by 'It must be a .....'
Hi Dave, the 501 (520) and 500 (530) sprocket splines/size are all the same; 12 splines with the diameters just below the 20mm and 18mm (I measured the shaft).
They all use the same spring/stop ring 22-01-54 as the 250 single which uses a 19-01-29 sprocket.
Trust this helps, Ian
PS As Mark says the 501 sprocket is 19-01-39

Re: Front Sprocket details

Posted: 23 Oct 2019 06:05
by davel182
Thanks Ian (and Mark). Just what I needed to know. 530 would be OTT for the 250 but I think 520 might do the job. I'll order one.

Re: Front Sprocket details

Posted: 23 Oct 2019 18:52
by norbert
520 is ok for all our bikes.
The last 3 sprockets I bought for the 500/501/250T all came without the stop ring. You can mount them without that ring, never had problems because of that. The only thing is to get the sprocket off when wasted, is that your need an extractor (three arms). To be able to use the extractor the chain must be off, because ther is only little space. So better use a chain with a lock you can open, otherwise with an endless chain you have to cut the chain.
I was not able to find the stop-ring/spring anywhere. At my last sprocketchange I destroyed the old one to get that ring off and put it on the new one (because I had an endless chain in stock). But as I said, during years I used the sprockets without that ring witout problems for the chain alignment.

norbert

Re: Front Sprocket details

Posted: 24 Oct 2019 06:50
by davel182
Thanks Norbert. That is good to know. The batch of 250T sprockets that NLM had made (with boss welded to sprocket) are very poor (in my opinion) and just go on to the shaft too far when you tighten the nut.

Re: Front Sprocket details

Posted: 27 Oct 2019 14:52
by 'It must be a .....'
Hi, as I have a 500 engine apart, I looked at the fitting of the sprocket (tried 2) with and without the spring/stop ring fitted.
Without the ring the sprockets went on the shaft a further 0.5 mm, (push fit only as I didn't fit and tighten the nut).

Re: Front Sprocket details

Posted: 27 Oct 2019 16:09
by norbert
That´s interesting, I never realy controled that. I think with 0,5 mm we can live, don´t we?

Re: Front Sprocket details

Posted: 27 Oct 2019 16:43
by davel182
Just so I'm clear, do the new 501 sprockets (19.01.39) have a groove for the ring or not? I have the ring from the original sprocket so I could fit that if they have. Thanks for all the input. Dave.

Re: Front Sprocket details

Posted: 27 Oct 2019 19:53
by 'It must be a .....'
Yes the e 501 sprocket has a groove and you can reuse the spring/stop ring, but they can be very difficult to remove and really go flying so be careful.

Re: Front Sprocket details

Posted: 28 Oct 2019 08:24
by davel182
Thanks for the warning but I already found that out! Luckily I managed to find it. Actually Mdina have the part listed (20 units) so I may order one with the spocket. Thanks again for all the information.

Re: Front Sprocket details

Posted: 05 Dec 2019 16:19
by davel182
Just a word of warning. I did indeed order a stop ring along with the sprocket but the new ring is bigger and does not fit in the groove (I did cut a bit off but it still got damaged during fitting) so better to be careful with the old one.

Re: Front Sprocket details

Posted: 20 Oct 2023 13:59
by mikebn
hello i have splined front sprockets 520 and 530 12 splines for 20mm shafet all new