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  #2941  
Old 01-13-2012, 01:22 PM
young grease monkey young grease monkey is offline
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Default Re: what did you do to your motor bike today?

the reason it doesn't leak is that the head is thin enough it will bend when you torque it down. it is bad for the head. can someone else back me up? just because it works, doesn't mean it's a good way to do it.and if you get loeaks because one isn't torqued the same, that diffinetly means they are not flat. you will get no leaks if one bolt is torqued to only 5 ft/lb, but it will loosen quickly, if you have a good flat surface.
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  #2942  
Old 01-13-2012, 06:53 PM
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Default Re: what did you do to your motor bike today?

Well, using a sanding pad is a bad idea because what you end up with is two convex surfaces that your trying to seal. A pad sander has a tendency to round off the edges because theres nothing to support the pad so the edge of the pad will exert more pressure along the edge over removing material from the center because there's more pad to resist deforming. This tendency gets more pronounced the further from the boltholes you get. It will seal ok at first but the problem is insuffecent contact area for both heat transfer and to prevent walk. Walk is when the head squirms around under heat and can actually move quite a bit, mechanically speaking. Eventually you will get a loss of compression from leaking but.. if you re-torque every two tanks or so and do it cold you should be ok...

And just about any piece of glass will work. It doesn't have to be 1/2" bullet proof glass. I use a mirror. NAPA has packs of wet/dry sandpaper from like 220-400 and 600-1000 grit I think it is. That and some oil and follow a guide and you will be successful. You don't have to grind hard, the oiled wet/dry cuts very well. Just because you don't see huge results it's still working. I actually stop at 400 grit because I use Permatex Spray Copper Form-A-Gasket to help seal. I've used it in my race motors for years and have never had a gasket leak.

I also have lapped computer processors and heatsinks. You do need to do those up to 2000 grit so they take much longer to do than a head and jug in a HT motor
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  #2943  
Old 01-14-2012, 06:34 AM
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DaveC DaveC is offline
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Default Re: what did you do to your motor bike today?

Quote:
Originally Posted by Scootmeister View Post
...The wheel fits perfectly on my Giant Stiletto now that I stretched the rear frame by 1 1/2 " with a screw jack I picked up at a junk store for $3. Tomorrow I'll true the wheel and install it.
This has stuck in my head for days. How the **** did you strech a steel frame 1 1/2" with a screw jack? It scares me half to death, there must be weakened or broken places in the tubing.


...or did you mean "spread" the frame?

Last edited by DaveC; 01-14-2012 at 06:44 AM.
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  #2944  
Old 01-14-2012, 05:36 PM
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breno breno is offline
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Default Re: what did you do to your motor bike today?

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Originally Posted by breno View Post
did the no no due to having too much time on my hands and went the whole way back to the header.. exhaust wrap is on.

Off the bat it is running different. I think it may be too lean in the mid range so I'll play with that tomorrow.
Found that the exhaust wrap had def. made it run leaner but I have also lapped the head down and changed the plug to a BP6HS. The pic is after a wot run so Ill be going back to a 75Main jet in the 18mm mikuni and have a fiddle with the needle setting if needed.
Might even play with the pilot jet for the low end again just got a 15 pilot jet interested to see how it goes coming from the 20 as I can still see a little blue smoke just off idle and its not that smooth at 1/4 throttle when going slow. Failing that I'll be taking a file to the slide as I found out apparently I cannot buy different size needles and slides from the fella here in Australia due to them just being a "cheap" carb that is used for mini bikes and what not that ppl dont really go to that length of effort playing with them...in short theres no market for him to keep them in stock..pita

Anyways tried to do a compression test last night and it was pretty much impossible with the crappy tester I had. Couldnt get a good enoough seal even with thread tape and tightening the **** out of it (I was using soapy water which was sprayed on to check for leaks). Ended up getting a highest reading of 140psi and I am still not confident that it wasnt leaking as I could see bubbles still. The 1st few times I tried I was only getting 75psi but I had a sneaking suspicion it was telling me porkies hence the soapy water method. Anyway anything over 140psi is good enough for me
The new style magneto should turn up tomorrow thank goodness.

Cant wait to have this bike 100% dialled in sooo dam close its eating at me.lol
Wont suprise me at all if it'll tip over 65km/hr with the 44 tooth if it does I'll have someone drive beside me and record it..keeping in mind I'm 6ft 5 and weigh 105kg should be a solid effort but I think its achievable.
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  #2945  
Old 01-14-2012, 07:51 PM
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Default Re: what did you do to your motor bike today?

I swapped brake pads front and back for new ones today, made a minor adjustment to the clutch, lubed the gearbox and went for a short ride after tweaking the brakes. It now stops comfortably within the thirty foot length I marked out. Had to watch it in the shady areas, we actually had snow last night in Vancouver so there's a few slick spots and a small patch or two of it left on the pavement.
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  #2946  
Old 01-14-2012, 09:41 PM
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rustycase rustycase is offline
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Default Re: what did you do to your motor bike today?

Yes, I also agree that using an orbital sander to lap a cylinder head is probably NOT the best idea. It will never be flat like when done on a glass plate.

Which is not to say it will not provide results better than a factory stock ht! lol

Best
rc
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  #2947  
Old 01-14-2012, 10:13 PM
Fugi93 Fugi93 is offline
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Default Re: what did you do to your motor bike today?

I opened up my new HOOT G5 gearbox for inspection. Found a defective spring on the clutch and removed it and and put it back together with only 3 springs. Takes off like a car now. I can now cruise at 4 mph with no clutch slippage. I am thrilled at how it truned out - all by accident! It took 14 mph to quit slipping before.



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  #2948  
Old 01-15-2012, 03:05 PM
5-7HEAVEN 5-7HEAVEN is offline
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Default Re: what did you do to your motor bike today?

I had mistakenly put too much oil in the tank, so my fuel/air ratio was @ 50:1. Carb adjustments were made to let the engine run better. After 5 days of commuting, I was down almost 60 ounces. I decided to add another 2 quarts of gas. Mixing this amount with 100:1 would raise my incorrect mix better than 83:1 f/a ratio.

After the fillup, the bike wouldn't idle. Being that I would be riding on the sidewalk to McD's down the hill, I left my tools and backpack @ home. Fortunately, I was able to use my fingernail to adjust the carb adjustments.

Bike riding fine now, ready for the commute on Monday.
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  #2949  
Old 01-15-2012, 05:06 PM
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andrewflores17 andrewflores17 is offline
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Default Re: what did you do to your motor bike today?

road my bike to the local park about a 9 mile round trip about half way through realized i should have put something warmer on my head than a ball cap ears nearly froze off brrr
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Last edited by andrewflores17; 01-15-2012 at 10:15 PM. Reason: spelt road rode
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  #2950  
Old 01-15-2012, 07:51 PM
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isldtime isldtime is offline
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Default Re: what did you do to your motor bike today?

Rode It..

Really over the last week I've added a suspension seat post and upgraded the front V-brake to quality parts and the rear from center pull to quality V-brake. Made a big diff.
Every time I ride it now it runs and rides better and better. Up to about 20 miles on it now and no major problems but the pre-flight is the most important item.
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