Bill DeLong's RC Blog

Monday, January 20, 2025

Intro to Nitro

I have close to 15 years of RC club racing experience at the time of this writing, though the only nitro engine experience I have was flying .40 nitro planes in the 90's and being a pit man for many racers in my area for the past 5+ years. If you are reading this post and are considering to get into the nitro classes then I would encourage you to hold off and gain as much experience in the electric classes first and buddy with a nitro guy to be his pit man for a while before you buy a nitro kit. This will give you the basic fundamentals of how to properly start/stop, tune and refuel a nitro before diving into the deep end. You should already have a solid setup on the electric version of the same platform you're racing so the only thing "new" to you will be how to drive a nitro instead of electric. Preferably you'll already be a seasoned driver with reasonable consistency ratings.

My goal is for this to be a guide on how to get started and a buyers guide.

$50-$80 - Pit Caddy Bag: This is more of a personal preference and doesn't really matter which brand bag you buy, I am using the HB Racing bag which is one of the larger bags in the industry with lots of large velcro pockets and dedicated slots to store virtually every nitro specific accessory I need on pit lane.
$20-$30 - Glow Starter: This is a critical tool that you don't want to go cheap. I can't tell you how many times I've seen these fail at the track so it's important to always have a backup ready, especially if you have an inexperienced pit person who accidentally walks off with your primary starter. I have learned the the TLR brand is generally become the most trusted glow starter among dozens of racers that I've pit for over the years. It's extremely important to put BOTH of your glow starters on the charger the night before every race event!
$10-$15 - P3 Glow Plugs - Hot: This is another crucial part that you don't want to go cheap on. The most reliable and longest lasting plug are OS branded plugs. You will save money in the long run buying a higher quality plug. You can save a few bucks with the Protek Samurai plugs which are rebranded OS plugs and there is no difference in performance between the Gold/Silver plugs so I run the Silver Samurai P3's myself. Generally you want to use a sacrificial plug for engine break in, then save that plug for practice, and always install a new plug just before the main of a big race event, so buy as many plugs as you need to account for however big events you plan to attend for the season. You can also re-use your "main-day-plug" several times with confidence if your collection of good working older plugs starts to grow
$5-$20 - Fuel Bottle: personal preference on this, some have cap holders which can be nice but I would always carry spare caps regardless as they tend to get lost and always carry a spare bottle as I often see these walk away by mistake and can be hard to track down
$70-$150 - Starter Box: wide array of features to consider, I recommend selecting a box that offers decent part support where belts tend to be damaged with newer motors during the break-in process. I run the ProTek box with recycled 4S LCG packs from my eBuggy. I also added spacers (per the instruction manual) under the bump stop to improve clearance to start the engine easier
$20-$40 - Temp Gun: personal preference on this essential tool, need to pre-heat the motor to 170° before every start and monitor temps so that engine comes off the track between 210°-230° to ensure a proper tune.
$20-$120 - Heat Gun or Engine Heater: Another personal preference here where engine heaters are convenient with a 12V supply or 3S Lipo but they can be cumbersome with having to carry an extra battery and cord dangling around. I prefer a heat gun which typically takes less than a minute to warm up and I prefer a cordless gun to avoid a messy cord as well as avoid popping circuit breakers at the track! Since I already own Ridgid brand tools/batteries I use their same cordless heat gun too which easily gets 4+ starts on a single 2Ah battery plus the attachment that comes with the heat gun is the perfect diameter for the engine head making this a great space saving option in my pit bag.
$7-$35 - Glow Wrench: This essential tool will serve many purposes so be sure it has both an 8mm socket for the glow plug as well as a 10mm socket for installing your clutch on the flywheel too
$4-$24 - Slotted Screwdriver: This essential tool is used to tune varioud needle valves on the engine, any driver will do and it personal preference on the quality of handle you prefer to use
$40-$80 - Fuel Stick: This is completely optional but can potentially save you precious seconds for a faster pit stop in the main if you want to be more competitive than using a fuel bottle
$90-$110 - Bearing Tool Kit: This essential tool will help you service your engine bearings where I use the RED's tool myself

bearing replacement is discussed by Adam Drake here:
Engine Break-In process is very complicated where I used the following resources for my first engine break-in:
https://www.rctech.net/forum/offroad-nitro-engine-forum/443611-engine-break-bible.html

Tuesday, January 7, 2025

Proposed ROAR Body Rule Changes

First week of December 2024, I went back and forth in email with several ROAR officials regarding the new rules they posted on their website. ROAR promised to raise my concerns in their board meeting in the second week of December then ghosted me.

https://www.roarracing.com/downloads/ROAR_Rule_Book.pdf

As of right now, ROAR expects all manufactures to pay 4 years in ROAR fees in advance, plus send each body plus an inspection fee which will cost roughly $1K to get 1 body approved initially and then after 4 years pay an additional $200/yr to keep their body on a list of approved bodies. Markings need to be stamped into the windshield of each body.

I explained that many drivers are tied into package deals where bodies/tires/wings/accessories are put into driver contracts, so if ROAR eliminates bodies from brands that used to be legal then drivers will be forced to violate their contracts and/or be forced to sign contracts with larger brands that can afford to pay the ROAR extortion fees.

The timing of their decision is in haste because they are not giving drivers time to test/apply to larger companies who are ROAR approved putting the industry into a catch-22. ROAR has the power to effectively put smaller companies out of business over this decision if tracks follow ROAR rules to the tee

These rules are not only truggy bodies, but buggy bodies too... so someone running a buggy body from a brand that was discontinued (or doesn't pay ROAR inspection fees) will be considered an illegal body without the stamp on the windshield.

I said that charging inspection fees is double dipping and that those costs should come from the ROAR fees that drivers already pay. This will prevent the threat of companies from going out of business so that racers pay any increase in fees to cover inspection expenses. Ultimately price increases will fall back to the drivers regardless when increasing unreasonable inspection fees.

Tuesday, December 31, 2024

Switch Eliminator

*** CLICK ON EACH PHOTO BELOW FOR FULL SIZE IMAGE ***

Special thanks to Danny Smith for sharing this idea!

There is a pre-wired kit available here:

https://klinikrc.com/shop-1/ols/products/klinik-rc-universal-18-switch-eliminator-set

I have chosen to solder up one myself using these XT60 connectors which offer a red rubber seal to improve the grip strength of the connection:

https://www.amazon.com/gp/product/B0BB2PD9CQ

I will be mounting the XT60 into an HB D8 WS radio tray using a dremel to carefully increase the opening:

I made sure to use blue thread lock when securing the screws:

Then used a 6" servo extension and spliced the negative lead in the middle as seen here:

After I soldered the black wires on each terminal, I used CA glue to secure the wiring to the side of the connector and placed a generous amount of glue over the metal braid to make sure the wires won't shear over time:

Then I drilled a small hole through each solder tab and soldered wire between for the bridge connector:

Final step was to place heat shrink over the bridge and that's all there is to it!

Monday, September 23, 2024

How to glue tires and recycle wheels/inserts

Although any brand of CA glue will work, I have had the best luck with LOCTITE 406 which is specially formulated to bond rubber with plastic:

https://www.amazon.com/s?k=loctite+406

I feel that 20ga glue tips work best for me with 406:

https://www.amazon.com/Industrial-Dispensing-Needles-Length-Interface/dp/B0D5PT38Z1

Some brands of tires require you to trim excess rubber along the beads from the mold process, if you don't trim the beads then you risk having the beads pop out of alignment during the gluing process!
For 1/8 (EVO) style beads I make sure to scuff the beads of both the rubber tires as well as the plastic wheels with the cylinder shaped stone bit on my rotary tool, then I prep both surfaces with alcohol swabs wait for them to be completely dry before gluing.

https://www.amazon.com/BD-Alcohol-Swabs-100-Each/dp/B000YMFUZO

I prefer to use silicone bands which last longer than rubber:

https://dialedhobbies.com/all-products/dialed-rc-1-8-buggy-tire-gluing-bands-4-detail

Then I apply a bead of glue between 1"-2" at a time, press then pull away the rubber to let the glue spread farther across the bead of both surfaces which makes it act like contact cement which makes an even stronger bond being careful to push the bead into the wheel and getting proper alignment before the glue sets by doing this within a few seconds for each glue spot ensuring 100% glue coverage on the bead

After I've gone the circumference of the wheel I drag the metal glue tip to build up a small even layer bead of glue as a second pass along the perimeter to act as a shield to lock the bead in place and prevent the rubber from tearing at the bead.
Also important to wipe excess glue from the applicator tip to prevent it from gumming up before gluing the next bead.

After every run, I will spot check the beads, it's not uncommon for the rubber to start to tear away and you may have to re-glue the tires where I use compressed air to remove any dirt/gunk and scrape away with a hobby knife then use an alcohol swab to de-grease the area before spot gluing any sections of bead that are separating.
To extend the life of my foam inserts I make it a point to wash my tires (only once) at the end of the race day which allows plenty of time for the inserts to completely dry before next use. Wet inserts are more prone to getting cracks and will fail prematurely!

If the track is ran wet(muddy) then I will lightly rinse my tires immediately after a run and try to save those tires for another race day being careful to have plenty of sets of tires on hand to minimize wear

Generally a set of inserts will last roughly 2+ hours of total run time before the foam starts to break down and lose its effectiveness, however there are many times where I might only get between 30-60 minutes of run time on a set of tires for abrasive track conditions!

I will often recycle my wheels/inserts which can save a small fortune, especially if your favorite brand sells rubber only:

https://dialedhobbies.com/rc-tires-wheels/dialed-rc-1-8-tires?clearCart=0
Be sure to inspect your wheels/inserts for damage to make sure they are suitable to be recycled, I often toss out the bad and keep the good condition parts to be mixed together later on.

I very carefully used curved scissors to cut the beads without damaging the foam insert and remove the foams, then soak the wheels in a tupperware container filled with acetone over night. Then the beads peel off effortlessly the next day

After removing the wheels from the acetone bath, I run them through a cycle in the dishwasher on the top rack then hit the beads with my dremel to flatten any rough gouges to reshape the bead if necessary. The following picture are 2 sets of recycled wheels/inserts along with a closeup of what the glue bead should look like with a second drag pass with the glue tip

Sunday, August 25, 2024

Which servo is best?

A while back I attended a race clinic hosted by Ryan Lutz and Joe Bornhorst... one of the topics of discussion was selecting a proper servo.

For starters they recommend selecting a brand that offers replacement gear sets as a bare minimum, and if budget allows, consider aluminum case servos or at least a brand that sells replacement cases should you tear a mounting tab in a nasty crash. Metal gears are a must, with titanium being a pinch more durable than steel in general. They also said everyone's reaction time is different and most folks should select a speed somewhere between 0.08 - 0.12 sec/60° and then use the "steering speed" feature on the radio to dial back the servo speed for your desired reaction time.

It's a good idea to first look at setup sheets to see what size servos folks are using for the class you plan to race... i.e. get a lighter low profile servo is less weight up front is desired (typically used in 1/10 stock classes) or select a heavier standard servo with full aluminum case to add more weight up front to get more steering response. There is no single right/wrong answer, just a bunch of variables to consider when making your selection.

For a budget minded driver, I'd consider the EcoPower WP120T just to start out with, replacement gear sets and servo cases are very reasonably priced for those who require buying from a US retailer with a reputable 1 year warranty.

If you are willing to restrict yourself to a 30 day warranty, then consider the OEM for the EcoPower 120T which are JX branded servos. The replacement gear sets are 100% compatible between both servos.

If you want the same servo enclosed in a solid aluminum case then consider the JX HV7232MG servo

If you want peace of mind then I highly recommend the ECO Power WP250T which is the most recent release having some upgraded internals with a different gear set.

Thursday, March 19, 2020

Which surface radio is the best?

There is no single radio system that is going to be "The Best" for everyone, but I will do my best to break down some features to help you decide which system has the potential to be "The Best For You" based on your own requirements.

Before you even begin selecting a system, I feel that it's very important to understand the technologies/features that are available and then you can begin ruling on which points are the most important as you begin your search. I've ordered each option by level of personal importance to me:

Which Spread Spectrum Modulation?
If you will be driving all by yourself, then this consideration is probably irrelevant, however, if you will be using your system in a large group with other radio systems present (i.e. Club Racing) then there is a risk of overlapping frequencies and/or limited range issues with your system which can cause severe delays in the input/response, this is called "Glitching". I have experienced varying levels of glitching with every single system that I have personally tested which use DSSS or "Direct Sequencing Spread Spectrum". Basically any system that has the letter "D" anywhere in the identification of the type of modulation. For example:

FlySky = AFHDS, AFHDS-2A
Spektrum = DSM, DSM2, DSMR
Radiopost = SDS, SDSTM (went out of business around 2018)

For a noisy environment, FHSS offers a better option to mitigate any risks of glitching, more specific details are explained here:
http://www.rcmodelreviews.com/spreadspectrum01.shtml
and here:
DSM/DSSS vs. FHSS 2.4GHz Modulations - FASST explained as well (9 min 53 sec)

I personally feel more comfortable recommending a system that uses FHSS and caution to stay away from any system that uses any flavor of DSSS just to play it safe.
HiTEC ditched DSSS (Aggressor series) and have since switched to using FHSS with the latest release of their Lynx 4S... Kudos to HiTEC for meeting the consumer's needs!
GFSK is a newer flavor of FHSS.
AFHD3 - Newest from Fly Sky NB4 which has fixed all known issues from it's predecessors, dozens of racers use this system in my are (myself included) without any glitching!

Telemetry
The use of telemetry is generally prohibited in almost all levels of organized racing, so be careful not to get suckered into having this set of features as you may risk being disqualified if you get caught using them at a racing venue. On the flip side, if you are just bashing around or would like to quickly check your temps for tuning purposes, then it can be handy to have an alarm sound if your electronics get too hot. Other important telemetry features include on-board voltage readings as well as speed sensors.

*** There have been complaints against Spektrum for limited effective range of telemetry readings being around 30' from the Tx

Features

How many model memories do you need?
How expensive are spare Rx's?
Does it include steering speed? Many low end systems do not include this feature which is the single most important feature to me!
How many characters do you need in your model names, and how long do the names need to be?
How fast/precise/smooth is the radio?
Is the screen large enough and easy to read in direct sunlight?
Are dual rates adjustable for each channel direction?
Are exponential rates available?
Is there a timer/stopwatch/alarm integrated?
How many channels do you need and/or mixing?
Does it include a fail safe?
Does it include a DSC port for simulator racing with VRC?
Does it accept rechargeable batteries and if so is there an external charger port?
Does the Rx accept HV?

Ergonomics - "Ergos"

How comfortable is the radio to hold?
What adjustments (if any) can be made to make the radio more comfortable?
Can the spring tension be adjusted on the steering and throttle?
Can the trigger be adjusted so that it's closer to the grip for smaller hands?
Is there a drop down available for the steering wheel?
Can the steering wheel be rotated into various angles?
How heavy is the radio? Can lighter lithium batteries be installed?
Are there replacement grips and or any soft rubber parts that are interchangeable to help increase comfort?
Are there different size steering wheels available to accommodate smaller hands?
Are there quick trim buttons easily accessible from the steering wheel?

Can you reasonably make trim adjustments without having to look at the radio, such that adjustments can be made during the middle of a race?

It's common for a car to lose trim setting after a crash.

Integrated Gyro
Gyros provide counter steer to help improve corner tracking which is best suited for drifting and/or low traction conditions. They are typically not allowed in racing as they significantly improve the handling to prevent the car from spinning out on a tight corner.

Radiolink: 3rd channel adjustment effects steering input only
Spektrum: 3rd channel adjustment effects both steering and throttle equally with the DX2E, you can't mix control bias to remove effect from throttle without also removing effect from steering. The DX4/5 series allows independent gain adjustments
KO Propo: 3rd and 4th channels control steering and throttle gain independently giving full flexibility of the gyro across both channels

Customer Support
Almost all brands of radios are manufactured overseas, however a few "name brands" have distributors in the US who cater to sales of their radios within their channel to ensure the highest level of customer support is honored. Some distributors will scan the serial number for each radio and will refuse warranty to any radio that was not distributed through the US channel. Plan to ship your radio for service from the same distribution channel you purchased from.

Price

Brand

Model

Modulation

TxVR

RxVR

Chg
Port

Str
Spd

Ch
Mix

Rx
Cost

Notes

$21