Reed valve with extended intake

[max350]

Quote Originally Posted by Fabian View Post

From what i understand, you can't use stainless steel in aluminium because it creates a galvanic reaction; corroding away aluminium...

That's interesting, I hadn't heard of this before. This link provides a little more detail:
http://www.bssa.org.uk/topics.php?article=89

Hardly a problem, stainless steel in aluminium ! (secure with Loctite), how long do you plan to use your MBC?

 

[Fabian]

You have a good point.

I am just going by the advise of staff at my local bolt and fasteners retailer.

 

[seb1008]

I used what I thought was red locktite on the Alan bolts that hold the 17 and 10 tooth sprockets on the jackshaft. Stripped the Alan wrench trying to free them tried to drill it out but none of the bits will drill through it only got partially through. The supposed cobalt drills I bought from england do not even scratch the metal.
Stupid mistake on my part I know.
Does anyone have an idea how to get the sprockets off the shaft.

 

[Fabian]

Loctite comes in different thread lock specifications; the most common types being "low strength 222, medium strength 243 and high strength 263.

My experience has show that a well prepared and spotlessly clean surface will have Loctite 243 creating a very strong bond that requires localised heating of the part to remove the fastener; and if not done, you will damage the Allen Key trying to remove the bolt.
Loctite 263 is diabolically strong as a thread locking compound and you "must" put more heat into the part to remove the fastener.

The other thing you will need when removing the 17 tooth sprocket (if a liberal amount of Loctite 243 has been used) is a small gear puller with a 100mm or 4 inch spread.
To give the gear puller a prepared place to locate, take a 4mm drill bit and just barely drill into the very centre of the jackshaft shaft. This will allow the conical tip of the gear puller a place to sit when applying screw pressure on the shaft.

When i assemble a jackshaft kit, the first thing i do is head over to my next door neighbours house, to use his lathe for the purpose of drilling the centre of the jackshaft with a 4mm drill bit (for an indentation on the other side of the shaft and a 1 inch deep hole on the other side) that allows the tapping an M5 thread. This serves two purposes: a) it lets me to install a translucent disk chain guard on the right hand side of the jackshaft b) it allows the gear puller tip a place to locate.

I wished SickBikeParts would do this as standard equipment, because i can't begin to think how many people have bashed the sh!t out of their jackshaft kit trying to remove the left and right hand side sprockets with a hammer, and then butchered the kit totally by getting a bigger hammer.





Just make sure that the grub screws are fully backed away from the shaft before using the gear puller to remove the 17 tooth sprocket.
To remove the 10 tooth jackshaft sprocket, first remove the 17 tooth sprocket and slide the jackshaft shaft out of the kit. Now place the jackshaft in a vice, but don't tighten the jaws on the shaft.
The 10 tooth sprocket will be resting on the top of the vice jaws.
Take a hex socket that is smaller than the diameter of the jackshaft and use a hammer to drive the shaft from the (pre-heated) 10 tooth sprocket.

If you use this process, there will be far less bad language thrown around the garage.

 

[seb1008]

Thank you for this sensible reply Fabian. I am going to call sick bike parts tomorrow and see if they will sell me the shaft and bearings and if they will I am going to grind the shaft apart in the center and put it back together the way you described. I have a new 17 tooth and the nine tooth for the other side already so all I need is the shaft and bearings.

 

[FurryOnTheInside]

Excuse me if this is obvious but
Why can't the gear puller be used to remove the right hand side 10T sprocket, too?

 

[Fabian]

Because you will need a smaller gear puller to remove the 10 tooth sprocket; the arms of a 4 inch gear puller will slip off the smaller radius.

Using the method i have described, allows you to get away with purchasing only "one" gear puller, instead of "two".

 

[FurryOnTheInside]

Ah ha! Thanks.
Do you reckon a 3" would do it though? As they're nearly all only sold in sets of 3 (3", 4" and 6") on FleaBay (UK).
I guess I'll find out anyway.

 

[Fabian]

A 3" gear puller should do the job.

I just bough a single gear puller because i have no real use for the thing other than removing the 17 tooth sprocket on the jackshaft.

 

[HeadSmess]

grind out broken hi tensile "undrillable" bolts with carbide drills,endmills, burrs in the die grinder/dremel etc. once theres a hole, you can use an extractor or just keep grinding if its still being recalcitrant. (yay, i always wanted to use that word...)

find someone with a spark eroder...

try sticking an arc welder rod to it... usually heats it up enough to burn out the loctite at the same time but can cause serious damage...

grind the heads off, pull the sprockets off, and hopefully theres enough stump left to grab with vice grips, after having heated them with a blowtorch to soften the loctite. always apply heat they come out like theyre greased then

if at first you dont succeed... get a bigger hammer

i always liked the semi flexible blue stuff or just plain silicone for holding bolts that are subject to vibration and or have to be removed occasionally... in my mind the stuff that sets hard will always be brittle. oh, and chuck in some thermal expansion cycles...

the only thing to keep in mind is as fabian says...not to damage the ends of shafts and or threads. dont hit them directly, but use a drift of some type. the number of left hand threads ive had to file back to size....grrr. not many people even know what a thread file is when they see one...