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 Estrella Technik
Norbritt Offline

Neuling

Beiträge: 18

28.06.2022 00:10
16 tooth sprocket change Antworten

Hi Forum,
Anyone have experience of changing the front 15 tooth sprocket for a 16 tooth version to slightly increase the top speed. What effect did the drop in torque have on the acceleration? 1st gear has always seemed a bit low anyway I always seem to change up within 30 or 40 meters of moving off.
Regards
Norbritt

Lambrella Offline

Sternchen

Beiträge: 282

28.06.2022 08:15
#2 RE: 16 tooth sprocket change Antworten

Hello Norbritt,
When I changed from the original 14 to 15, everything went a little better. Then I put in 16, which only reduced rev but did not give extra speed. I was already told here in the forum that my carburettor might not give enough power to the emgine. So try 16! I might have a look at the parts of my carb.
Make sure you get a sprocket in the correct width/thickness.
Roger

Soulie Offline

Der Laminator und Sattel-Max


Beiträge: 3.206

28.06.2022 12:13
#3 RE: 16 tooth sprocket change Antworten

Zitat von Lambrella im Beitrag #2
Make sure you get a sprocket in the correct width/thickness.

That's important. The aftermarket sprockets are too slim on the engine side. The result is leaking oil.
You can read about this problem and how to avoid it here in the technik part.

Norbritt Offline

Neuling

Beiträge: 18

28.06.2022 21:56
#4 RE: 16 tooth sprocket change Antworten

Hi Gentlemen,
Thanks for the feedback ref the 16 tooth sprocket change. I have noted other comments on the forum regarding the thickness of aftermarket sprockets leading to oil leaks. I have a new sprocket on order ( a rubber damper type) and will check the thickness against the original. I note that behind the sprocket is a collar and beyond that an O-Ring which I assume is what actually keeps the oil in; presumably it is the pressure of the collar against this ring that effects the seal therefore with the sprocket tightened down fully if the sprocket is not thick enough an oil leak results. As my machine is totally leak free present I may well leave well enough alone.I am not particularly interested in extra speed just in lowering the rpm for the sort of speeds I do use on longer runs.
Regards Norbritt

Lambrella Offline

Sternchen

Beiträge: 282

29.06.2022 20:07
#5 RE: 16 tooth sprocket change Antworten

…so your Last sentence shows you should put in the 16-Part!

Norbritt Offline

Neuling

Beiträge: 18

14.07.2022 00:54
#6 RE: 16 tooth sprocket change Antworten

Greetings all,
I spent this afternoon fitting the 16 tooth sprocket to the bike plus a new chain. I know I should really have changed the rear sprocket as well but it is in pretty good condition so it is for a later date. Comparing the sprocket that came off with the new one I noted 1. the original has a rebate approximately 2mm deep machined into the inside face of the sprocket into which the collar on the drive shaft fits; this I imagine stabilizes the sprocket on the shaft. The after market version is completely flat. The original sprocket thickness measured from inside the rebate to the outer face is 8.8mm with an overall thickness of 11.7mm the after market version is 8.5mm with no rebate. The removed sprocket also appeared to have originally had a rubber damper which had disintergrated and disappeared. For what good it might do I fitted 4 .5mm shims on the shaft before installing the new sprocket, this brings the front face of the sprocket nicely into position to fit the retaining plate. The whole arrangement seems rather odd, why not just one large nut and fold flat washer to hold the whole thing on.
I am not certain where the problem of the oil leaks come from as the drive shaft is fitted with an oil seal seated in the crankcase and seems to have no contact with the sprocket at all. I shall keep a close watch for any leaks as the kms build up. Naturally as always when doing on job you discover another. On removing the chain cover I discovered the plastic chain slider was partially broken; it still works which is a good thing as I can find no trace of one listed on the parts manual.
Finally how does the bike go now? A short road test showed that the acceleration seemed virtually unaffected and 4th gear was now rather more useful with 5th a bit more like an overdrive meaning that at the sort of speeds I use most (90/95 kph) there is a usefull drop in RPM.
Sadly I am also being tempted by a spotless W800; having once had a W650 I know how good these bikes are; trouble is the cost and I would not find it so easy to work on as the Estella.
Enjoy your riding.
Norbrit

Soulie Offline

Der Laminator und Sattel-Max


Beiträge: 3.206

14.07.2022 08:12
#7 RE: 16 tooth sprocket change Antworten

If you fitted the exact difference between the old and new sprocket with shims, then there will be no oil leaks.
I have both, w650 and Estrella, but I hardly use the 'big' bike'. Maybe in the fall. It's a pity,
since the bikes have to be ridden. But its far too hot right now.

Cheers
Soulie

Norbritt Offline

Neuling

Beiträge: 18

15.07.2022 21:24
#8 RE: 16 tooth sprocket change Antworten

Hi All,
I have now done approx 200 kms with the new sprocket and it is a great improvement. The engine sounds a lot more comfortable when cruising and the alteration of the ratios to the lower gears is very usefull. I would stress though I live in eastern England with very few significant hills I would imagine it would not suit as well in very hilly country and would probably mean a lot more up and down through the gears.
I have decided not to be lured by the W800 I am pretty certain with two bikes it would spend too much time in the garage.
Regards Norbrit

Soulie Offline

Der Laminator und Sattel-Max


Beiträge: 3.206

16.07.2022 09:44
#9 RE: 16 tooth sprocket change Antworten

You're right. My Estrella has to climb ~ 800 meters every day, some of them quite steep.
That's why I use the small sprocket. It fits nicely, and since I don't go faster than 70 kms
(glad, when I can go 50 - those damn slow-moving tourists, who enjoy the lakeside view)
I don't mind the higher revs.
I even changed the sprocket of my Honda XBR 500 for a smaller one and find it comfy.

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