Paging Kurlon - XR100R

[breakdirt916]

stock

[breakdirt916]

okay...I couldn't take it anymore...just got an '02 XR100R...I wanted an '01+ because they look newer w' the tank shrouds...plus I got a "sure, cool, I'll take it" price

no dirt duty, just mini moto track and wheeliez fo' days/#bikelife

can't find any $50 XR80 front wheels on fleabay just yet...but w/e was in the earlier post is what I'm gonna do (16" rim, BT45's, handguards, ims shifter, fork spacers/oil, catch can)

[loudbeard]

Sweet, bruh. FWIW, I haven't seen any XR80 front wheels for less than about $100 complete. Still worth it though.

Mine is progressing slowly. I ordered a 120 kit for $130, and the picture appeared to be complete. Upon arrival, it didn't have the jug. My dumbass fault for not reading the fine print, but in my defense I've always likes pictures better than words.

Returned that, got a gasket kit, carb rebuild kit, and new set of rings for about $80. At $130, the big bore kit was worth it, at $270...not so much.

For the short term, suspension work be damned. This is a budget bike so I'm going to just ride it and read about it before I spend anymore money on it.

Got into reassembly with Degsy week before last and ended up at a point where we needed a shop manual, because pictures, so I got a one on eBay and it came in last week. Just trying to find an evening that works for both of us to finish putting it back together. It should make its debut at Round 4.

[loudbeard]

Life! She's all back together and running. Still need to adjust the carb, I'll swing by Degsy's this afternoon and finish up.

Still need to decide if I'm going to get a 16" front or not. Plan is to run mostly at Wachusett Valley and I hear a lot of the guys up there just run Trail Wings on stock wheels. It's definitely the cheaper route.

[Tas]

Wachusett Valley is running this weekend so the sign said when I drove by yesterday on my way to Woodcraft.

[TheIglu]

I'd love to try this out on Sunday. Stupid no bike to use. Maybe I'll rent one.

[breakdirt916]

trailwings on oem rim sizes should be fine for flat track...I vaguely remember hearing that matching wheel sizes is a better setup, but it's an XR100, so meh

I am going to run the bt45...a quick ebay search shows that 100 width tires are the narrowest that they get...so I'm just going to run a matching front/rear size in 100/90-16

Previous owner: oh yeah, hey, let's just drill a buncha holes in the airbox and the bike will get faster



it's way faster, trust me...except that it doesn't idle, loud, it cuts out under WOT, and is tough to start. But it's faster!

nope...replaced the airbox cover and it still wants to die at idle...the gutted exhaust is just too much airflow. IIRC, I had the same issue w' my '03 that had an FMF system with no jetting changes. Previous owner said "ohhh, it just need the carb cleaned or something like that. If I do it, I'm just going to raise the price." I upped that pilot jet and she idled smoother than a lawnmower....sounded like one too.

jets, air filter, and hand guards on the way...

I wonder if the pegs will scrape @ the sumo track and throw me on my ass?

[Kurlon]

Skip the 100, go 110. The 'V' rated BT45s have much better rubber. I'm running them on my skinny dirtbike rims, they work great.

Pinned: Good luck finding a cheap XR80 front wheel right now, the ones that are floating around are typically way overpriced as the XR100 sumo market has sucked up all the cheap ones.

[loudbeard]

Per Wachusett Valley, they're racing this weekend indeed. I'm committed already, however the following weekend they have family/practice day Saturday 12-8, Sunday 12-5. I'll be there most of the day on Saturday doing a shake down. Iglu, you're more than welcome to come give it a rip. Dove will be there too, he's going to rent a bike for the day.

Last I checked on XR80 wheels they could be had around $100-150. I think just for flat track I'll be fine with stock wheels and TW's. If I end up taking my oversized self up to Boxshop I think a better setup might be in order.

[TheIglu]

Any word on how much it was to rent a bike for the day? May just do that instead of stealing yours away from you if the price is reasonable.

I'm down to clown for the FFD. Bout time I ride this track, I drive by it twice a day.

[loudbeard]

Looks like $125 for the day

[FirstDuc-1098]

...they have family/practice day Saturday 12-8, Sunday 12-5. I'll be there most of the day on Saturday doing a shake down...

hmmm... I may have to spin by. Not to ride, but to have a good laugh at the big monkey on the little bike going boom.

[cdovego]

hmmm... I may have to spin by. Not to ride, but to have a good laugh at the big monkey on the little bike going boom.

We'll be banging bars - it'll be worth stopping by to see.

[Tas]

hmmm... I may have to spin by. Not to ride, but to have a good laugh at the big monkey on the little bike going boom.

I also might stop by, that would be a site to see but I hear you can teach monkeys to do most anything.

[loudbeard]

OK so I'll ping you guys for some basic carb tuning info, its all new to me, I'm of the fuel injected age.

Let's start by assuming that my factory jetting is sufficient to at least achieve normal operation. Maybe this isn't a correct assumption, correct me if I'm wrong.

I'm running a #95 main and #35 pilot. Have seen numerous info that with a stock engine, exhaust, and pipe guys are still going #105 main and #38 pilot. I'll consider that if my current setup is a fail.

Basically I have 2 options for adjustment; air-idle screw and throttle stop screw. Here's what's happening.

I can get the bike to idle fairly well but a bit on the high side. When I give it throttle, it bogs towards the top, then when I release the throttle it idles at a much higher speed. I can readjust the throttle stop to bring it down, then have to increase idle to keep it from stalling. Make sense?

I've made some adjustments with the air idle screw in both rich and lean directions without yielding much of a result.

So, suggestions?

[Kurlon]

Well, high or hanging up idle after closing the throttle is classic lean on the pilot symptoms. Being lean everywhere out of the crate is a Honda hallmark. (Yamaha dirtybikes too actually...) I'd throw a 38 pilot in, set your air-idle screw to 1.5 turns from fully closed and go from there.

You'll likely find the bike is happier with a fatter main as well, these machines are notoriously lean out of the crate.

[loudbeard]

Gotcha, thanks. I pretty much came to a stopping point with it after numerous adjustments in either direction didn't really yield any different results.

Looks like we're on to jetting.

[Kurlon]

Yeah, when you're too far one way on a jet, the adjuster can't swing things enough to change the behavior. What you want on the pilot is for the idle to return without dipping or hanging when you let the throttle snap closed.

Also, when trying to dial it in, make sure it's actually up to temp. Idling for 10 minutes isn't good enough, go out and do some hard acceleration up through a few gears a few times, THEN start adjusting idle speed and idle mix. Cold blooded is a massive, massive understatement on these bikes. Fattening up the jetting will help with that some.

[Tas]

A hanging idle can also indicate an air leak too can't it? Between the carb boot and cylinder? Was there an o-ring there?

When it's hanging you can squirt some WD-40 around the boot and if it drops fairly quickly then there is an air leak there.

[Kurlon]

Absolutely, both indicate too much air. Easy to test, get the bike started then spray some parts cleaner around the intake and see if the engine suddenly changes behavior.

[loudbeard]

I'll check for air leaks too. I can't say the air box is 100% sound, but the carb and intake pipe should definitely be good to go, I did a complete rebuild kit with all new rubber and paid close attention in assembly that gaskets stayed in place.

[Kurlon]

Eh, what happens on the airbox side of the equation, who cares. Leaks there just mean the potential for dirt getting in. It won't radically impact your tuning to have slight leaks on that side.

[breakdirt916]

K got it right...up the pilot to 38 and it won't stall when you back out that throttle stop. A bigger main will help with cutting out up top. I think even a 98 main is lean...so whatever is the next size up or th 105 should be good

[loudbeard]

Nice bruh

Just scooped up an XR80 front wheel from eBay, $85 shipped. Just need to snag a set of bridgestones and we're rolling. I'll pick up a few jets at bettencourts on Monday after work and see if I can get this thing running nicely.

[breakdirt916]

$85 is a deal!! Nice!