HELP! Is having a rev limiter necessary? Digital speedometer install.

i had one like that, it came out like this.
get a piece of brass rod about 1/4 inch and 1.5 inches long
strip the carb of anything that will burn/melt
chunk of plumbers solder with lead, also 1/4 inch long
solder flux down the hole then the solder then the brass rod
now HEAT THE CARB AREA till the solder melts, then a little more heat on the brass rod just to be sure
hold the rod centered till it's solid and unscrew it, mine was still very tight
i was surprised it worked but the next step was the garbage can, i reused that screw

 

One more thing. It might take more than one heat cycle for it to break loose. Be patient.

 

How does that work? I would expect the solder to break loose from the screw, solder is usually not that strong in my experience... by solder flux you mean the stuff that looks like some fat gel right? ...feel like I would be way over my head with that technique...

 

Ooo, now that's a new one - might try that one day. See no reason it shouldn't work.

 

If you can melt alumina with a butane torch hats off to you!

 

You're right about the butane. I use my propane torch in the kitchen, because I'm too cheap to own more than one torch...lol.

 

don't know how much torque that solder joint could take but once the head is stripped out you can't put any torque on it
i'm no welder but could you stick a welding rod to a steel screw ?

 

Not on mine......I’ve gone over redline a few times. Those who have been to CNYCC’s have seen it a few times

 

Mixture screws are brass.

 

Not always, but the OP's sure are.

 

VICTORY!!!!!!
(Penetrating oil for 2 days, didn’t need to apply heat, nerve wrecking dremel tool job....)

 

Once you get the carbs working properly and dial the idle mixture in, you should think about making a rubber cap (from the rubber "clay stuff" arts supply stores carry, Sculpey is one brand) to help protect the slot in the new mixture screw.

 

except the ones that are steel

 

that sounds like a job for a 3d printer

 

Yes! Definitely don’t want to have the same problem in future.

 

Maybe if I ever make time to learn how to do the CAD part. Summer is coming though, and I do have the desire.

 

You live and learn - never seen one myself.

 

Adjusted mix screws until I got the highest rpm with the least amount of weirdness ( revs up and down fast and doesn’t sputter, no backfires in exhaust).
I did a carb sync and the bike sounds absolutely amazing!!!
None of the old strange engine sounds, PLUS, all the headers get hot now! Firing on all cylinders!!!

TOOLS:
- 2 inch t-shirt strip with a few knots (one knot per 2-3 inches) drenched in 2-stroke oil to block the YICS port.
-tubes of equal length filled with 2 -stroke oil as a make-shift carb sync tool. Videos of similar stuff on YouTube.. ( using that is a bitch and a half, had to wait for the oils to set between each adjustment.. or just try to make them all stop moving where they are by adjusting carbs. Took about an hour just doing those adjustments...)

 

Next time you can skip blocking off the YICS ports. Use smaller diameter tubing inside each of the tubes going from the engine to the manometer so the pulses are dampened. Makes reading the oil levels easier.

 

People on here say blocking the YICS is super important, so they got to me. I know it's a debate long as life itsself Smaller tubing, great idea.


NOW.... I got more issues... a little bit of oil sweating from the upper part of my engine... I tried to block it with some metal filler, but it still sweats through when I run the bike... WHAT TO DO?

 

Metal filler is going to struggle there - what happens is that the pressure builds up behind it, and there is nothing stopping it lifting away.
I would drill and tap the plug, pull it and make a new one - maybe you have a machine shop locally that can make you one?
Tried chacal?

 

Would a helicoil work?

 

The thing is.. there was some brown "stuff" there before, and it looked really stupid.. So I removed it, since oil has been seeping out there. So it is possible, it WAS blocked..

What I'm cusious about is what the f*** that "port" is, why is it there? and why is it leaking?

 

Not in that application. Tapping the bore for a threaded plug (as the factory did in about 1/2 of the heads) will make for an oiltight seal, or a new plug can be pressed in.

 

That is where the oil gallery for the exhaust cam was drilled during production of the head. The plug was either a press fit, or a threaded bolt with sealant. Both were used by the factory to seal the oil gallery.
You have another set of plugs on the intake cam oil gallery.

 

This sucks tho, isn't drilling into that thing gonna put metal shavings inside the oil gallery then? Anybody know how deep that thing goes?

 

It must go all the way under the camshafts to feed oil to the cam journals. Misunderstood you mean the depth of the plug or threaded bolt.

 

1. YOU won't be doing the drilling, a machine shop will.

2. The drilling to remove the plug will not go all the way through the plug, it will be removed with a puller after there is a hole and threads made in the plug for the puller to grab. (this is the ideal method, but it dosen't always work. The alternative methods do produce chips that can potentially get into the oil gallery, but that is dealt with later).

If a threaded plug is used instead of a pressed-in plug the hole will be threaded with grease on the tap that will catch all of the chips. The oil gallery will then be flushed out from the inside of the passages (oil/ solvent/ metal cutting coolant (depending on the shop) will come out of the open end of the oil gallery, washing any remaining debris out with it).

3. It runs all the way out the other side of the head. You'll find another plug on the opposite side of the engine.

4. While not a common failure, it is one that machine shops around the word get to do on all sorts of machinery several times per year.

 

Thanks you K-moe! How expensive are machinists tho? I agree it’s scary to drill there and letting a professional do it would be best.. peace of mind and that

 

It's one of those jobs not hard to do, but easy to cock up. Drilling all the way through the plug would be classed as cockup No1. Don't be under the impression that any bike shop could do this job, it needs some (simple) but careful engineering.

 

That will vary. I was quoted $100 for a more difficult, but similar job to repair a messed up threaded hole and rebuild the part of it that was missing. Your job should not be more than that, and might be less. A replacement (used) head will cost more, and that's without shipping.
Call around and get quotes. Have the pic ready to email, and let them know that you have it.

 

Those metal epoxies will make a quick and painless repair. What have you got to lose?
I patched a broken water pump housing on the kids dirt bike, even had a chunk missing. Rode for a year then sold it with the repair still holding.

 

Like JB weld? I mean why not try right? Im suspecting it won’t work because of oil pressure, but wouldn’t cost me much to try..

 

Sorry for the delay, COVID got me depressed and out of money there for a while, but I’m back at it! Rode the bike with a leak for a while and had a really good time!

I went to a local cylinder service shop and paid 1300 nok (130 £ ish ) to block the oil leak! Pretty okey price, did it in one day.

The bike is now gangster with a gold tooth yo!
( great to be able to lean into a corner without having oil dripping onto the rear wheel hehe)

 

MORE ISSUES THO!

Like I said, I’ve been riding a bit, smaller trips. But issues occurred when I tried taking the bike in the highway.... engine started bogging down and eventually stopped. This happened a few times. First time I assumed it was out of fuel. The tank was low, but not empty. But I filled up and it started up again. Hmm curious. But it kept happening. It would bog out, I would then spend some time checking fuel lines, chokes system, air filters, battery... and then it would magically start again...

I started thinking it was a too large main jet, maybe high rpms was drowning the engine?

then I did some research and realized: this is the excavator symptoms of engine overheating .... I had filled too much oil when I did the oil change last year.... didn’t think it was that big of a problem right... hehehe. So, too a sample of the oil, to check the state of it: bubbles...... oil looks like whipped cream ...

Long story short, gonna do oil and oil filter change CORRECTLY... and pray to the MC gods that I haven’t done too much damage to the engine.

pray with me guys

 

Changing the oil and oil filter didnt help, still bogs out under acceleration and get difficult to start.

 

Turns out a clogged fuel filter can cause lean condition/overheating/bogging out. Replaced fuel filter with washable version. Rode bike all day without issues

 

… Rode bike a full season! Very happy with it! This winter I am replacing the strange xj handlebars with some MX bars.

ISSUE: I needed to stretch the cables from the handlebar. I bought a cable repair kit and some outer wire housing for bicycles and clutch wire at 1.5mm thickness. It operates fine now that I fitted it on the bike, but I can’t help but worry that the MUCH thinner clutch cable I fitted on will crumble under the force of the clutch… Is “clutch wire thickness” important? Or can I relax as long as it operates well for now?

(Good place to buy thick clutch cables anyone?)